Number of the day: 61490

Properties of the number 61490:

61490 = 2 × 5 × 11 × 13 × 43 is the 55304^th composite number and is squarefree.
61490 has 5 distinct prime factors, 32 divisors, 19 antidivisors and 20160 totatives.
61490 has an oblong digit sum 20 in base 10.
61490 = 66² + … + 77² is the sum of at least 2 consecutive positive squares in 1 way.
61490 is the sum of 2 positive triangular numbers.
61490 is the difference of 2 positive pentagonal numbers in 6 ways.
61490 = 29² + 40² + 243² is the sum of 3 positive squares.
61490² = 36894² + 49192² = 15136² + 59598² = 31218² + 52976² = 23650² + 56760² is the sum of 2 positive squares in 4 ways.
61490² is the sum of 3 positive squares.
61490 is a proper divisor of 859² - 1.

The number 61490 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A008957: Triangle of central factorial numbers T(2*n,2*n-2*k), k >= 0, n >= 1 (in Riordan's notation).
A028269: Distinct even elements in 3-Pascal triangle A028262 (by row).
A028270: Central elements in 3-Pascal triangle A028262 (by row).
A029617: Table read by rows: list of even numbers to the right of the central elements of the (2,3)-Pascal triangle A029600.
A029631: Even numbers to left of central elements of the (3,2)-Pascal triangle A029618.
A036969: Triangle read by rows: T(n,k) = T(n-1,k-1) + k^2*T(n-1,k), 1 < k <= n, T(n,1) = 1.
A081497: Duplicate of A028270.
A192754: Constant term of the reduction by x^2->x+1 of the polynomial p(n,x) defined below in Comments.
A255180: Number of partitions of n in which two summands (of each size) are designated.
A269945: Triangle read by rows, Stirling set numbers of order 2, T(n,n) = 1, T(n,k) = 0 if k<0 or k>n, otherwise T(n,k) = T(n-1,k-1)+k^2*T(n-1, k), for n>=0 and 0<=k<=n.