56615661504 has 140 divisors (see below), whose sum is σ = 169489773288. Its totient is φ = 18684864000.

The previous prime is 56615661499. The next prime is 56615661541. The reversal of 56615661504 is 40516651665.

56615661504 is a `hidden beast` number, since 566 + 15 + 66 + 15 + 0 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 56615661504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 469519 + ... + 577649.

Almost surely, 2^56615661504 is an apocalyptic number.

56615661504 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56615661504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84744886644).

56615661504 is an abundant number, since it is smaller than the sum of its proper divisors (112874111784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

56615661504 is a wasteful number, since it uses less digits than its factorization.

56615661504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108256 (or 108237 counting only the distinct ones).

The product of its (nonzero) digits is 648000, while the sum is 45.

The spelling of 56615661504 in words is "fifty-six billion, six hundred fifteen million, six hundred sixty-one thousand, five hundred four".