Number of the day: 346

Properties of the number 346:

346 = 2 × 173 is semiprime and squarefree.
346 has 2 distinct prime factors, 4 divisors, 11 antidivisors and 172 totatives.
346 has an emirp digit sum 13 in base 10.
346 has a Fibonacci digit sum 13 in base 10.
346 has an oblong digit product 72 in base 10.
Reversing the decimal digits of 346 results in a prime.
346 is the sum of 2 positive triangular numbers.
346 is the difference of 2 positive pentagonal numbers in 2 ways.
346 = 11² + 15² is the sum of 2 positive squares in 1 way.
346 = 3² + 9² + 16² is the sum of 3 positive squares.
346² = 104² + 330² is the sum of 2 positive squares in 1 way.
346² is the sum of 3 positive squares.
346 is a proper divisor of 691² - 1.
346 = '34' + '6' is the concatenation of 2 semiprime numbers.
346 is an emirpimes in (at least) the following bases: 3, 11, 13, 14, 16, 18, 19, 21, 23, 24, 25, 26, 29, 31, 32, 33, 34, 35, 38, 41, 43, 44, 45, 46, 50, 52, 55, 56, 68, 69, 71, 73, 79, 85, 89, 90, 91, 92, and 94.
346 is palindromic in (at least) the following bases: 9, 15, -23, and -69.
346 in base 4 = 11122 and consists of only the digits '1' and '2'.
346 in base 9 = 424 and consists of only the digits '2' and '4'.
346 in base 14 = 1aa and consists of only the digits '1' and 'a'.
346 in base 15 = 181 and consists of only the digits '1' and '8'.
346 in base 18 = 114 and consists of only the digits '1' and '4'.

The number 346 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A000172: Franel number a(n) = Sum_{k = 0..n} binomial(n,k)^3.
A004207: a(0) = 1, a(n) = sum of digits of all previous terms.
A006753: Smith (or joke) numbers: composite numbers n such that sum of digits of n = sum of digits of prime factors of n (counted with multiplicity).
A007811: Numbers n for which 10n+1, 10n+3, 10n+7 and 10n+9 are primes.
A100484: Even semiprimes.
A143164: Numbers with digitsum 13, in increasing order.
A161344: Numbers n with A033676(n)=2, where A033676 is the largest divisor <= sqrt(n).
A259934: Infinite sequence starting with a(0)=0 such that A049820(a(k)) = a(k-1) for all k>=1, where A049820(n) = n - (number of divisors of n).
A301678: Coordination sequence for node of type V1 in "krn" 2-D tiling (or net).
A301712: Coordination sequence for node of type V1 in "usm" 2-D tiling (or net).