Number of the day: 3927

Properties of the number 3927:

3927 = 3 × 7 × 11 × 17 is the 3382^th composite number and is squarefree.
3927 has 4 distinct prime factors, 16 divisors, 17 antidivisors and 1920 totatives.
3927 has a semiprime digit sum 21 in base 10.
3927 has a Fibonacci digit sum 21 in base 10.
3927 has a triangular digit sum 21 in base 10.
3927 has a triangular digit product 378 in base 10.
3927 = 1964² - 1963² = 656² - 653² = 284² - 277² = 184² - 173² = 124² - 107² = 104² - 83² = 76² - 43² = 64² - 13² is the difference of 2 nonnegative squares in 8 ways.
3927 is the difference of 2 positive pentagonal numbers in 2 ways.
3927 is not the sum of 3 positive squares.
3927² = 1848² + 3465² is the sum of 2 positive squares in 1 way.
3927² is the sum of 3 positive squares.
3927 is a proper divisor of 307² - 1.
3927 is palindromic in (at least) the following bases: 6, 36, 76, and -6.
3927 in base 4 = 331113 and consists of only the digits '1' and '3'.
3927 in base 12 = 2333 and consists of only the digits '2' and '3'.
3927 in base 35 = 377 and consists of only the digits '3' and '7'.
3927 in base 36 = 313 and consists of only the digits '1' and '3'.
3927 in base 62 = 11L and consists of only the digits '1' and 'L'.

The number 3927 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A006190: a(n) = 3*a(n-1) + a(n-2), with a(0)=0, a(1)=1.
A024966: 7 times triangular numbers: 7*n*(n+1)/2.
A026907: Triangular array T read by rows (9-diamondization of Pascal's triangle). Step 1: t(n,k) = sum of 9 entries in diamond-shaped subarray of Pascal's triangle having vertices C(n,k), C(n+4,k+2), C(n+2,k), C(n+2,k+2). Step 2: T(n,k) = t(n,k) - t(0,0) + 1.
A033568: Second pentagonal numbers with odd index: (2*n-1)*(3*n-1).
A089558: a(n)=A089551(n)/2.
A132355: Numbers of the form 9*h^2 + 2*h, for h an integer.
A138940: Indices n such that A019328(n) = Phi(n,10) is prime, where Phi is a cyclotomic polynomial.
A250676: T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction
A266055: T(n,k)=Number of nXk integer arrays with each element equal to the number of horizontal and antidiagonal neighbors less than or equal to itself.
A324315: Squarefree integers m > 1 such that if prime p divides m, then the sum of the base p digits of m is at least p.