### Properties of the number 2219:

2219 is a cyclic number.2219 = 7 × 317 is semiprime and squarefree.

2219 has 2 distinct prime factors, 4 divisors, 15 antidivisors and 1896 totatives.

2219 has a semiprime digit sum 14 in base 10.

2219 has a triangular digit product 36 in base 10.

Reversing the decimal digits of 2219 results in an emirpimes.

2219 = 1110

^{2}- 1109

^{2}= 162

^{2}- 155

^{2}is the difference of 2 nonnegative squares in 2 ways.

2219 is the difference of 2 positive pentagonal numbers in 2 ways.

2219 = 1

^{2}+ 3

^{2}+ 47

^{2}is the sum of 3 positive squares.

2219

^{2}= 525

^{2}+ 2156

^{2}is the sum of 2 positive squares in 1 way.

2219

^{2}is the sum of 3 positive squares.

2219 is a proper divisor of 1471

^{4}- 1.

2219 = '221' + '9' is the concatenation of 2 semiprime numbers.

2219 is an emirpimes in (at least) the following bases: 2, 4, 9, 10, 11, 12, 19, 21, 24, 28, 29, 34, 38, 40, 41, 42, 43, 45, 49, 51, 53, 62, 63, 69, 73, 76, 79, 80, 82, 83, 84, 85, 86, 93, 96, and 97.

2219 in base 23 = 44b and consists of only the digits '4' and 'b'.

### The number 2219 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.A002212: Number of restricted hexagonal polyominoes with n cells.

A091965: Triangle read by rows: T(n,k)=number of lattice paths from (0,0) to (n,k) that do not go below the line y=0 and consist of steps U=(1,1), D=(1,-1) and three types of steps H=(1,0) (left factors of 3-Motzkin steps).

A112815: Numbers n such that 7*LCM(1,2,3,...,n) equals the denominator of the n-th harmonic number H(n).

A145812: Odd positive integers a(n) such that for every odd integer m>1 there exists a unique representation of m as a sum of the form a(l)+2a(s)

A213207: Number of distinct products i*j*k over all triples (i,j,k) with |i| + |j| + |k| <= n.

A216994: Multiples of 7 such that the digit sum is divisible by 7.

A226623: Irregular array read by rows in which row n lists the smallest elements, in ascending order, of conjecturally all primitive cycles of positive integers under iteration by the Collatz-like 3x-k function, where k = A226630(n).

A226627: Irregular array read by rows. a(n) is the smallest starting value of a T_k trajectory that includes A226623(n), where T_k is the Collatz-like 3x-k function associated with A226623(n).

A237341: For k in {2,3,...,9} define a sequence as follows: a(0)=0; for n>=0, a(n+1)=a(n)+1, unless a(n) ends in k, in which case a(n+1) is obtained by replacing the last digit of a(n) with the digit(s) of k^2. This is k(4).

A259515: T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with each 2X2 subblock having clockwise pattern 0000 0001 0101 0111

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