56487981 has 16 divisors (see below), whose sum is σ = 82967040. Its totient is φ = 33900720.

The previous prime is 56487979. The next prime is 56487989. The reversal of 56487981 is 18978465.

It is not a de Polignac number, because 56487981 - 2¹ = 56487979 is a prime.

It is a super-2 number, since 2×56487981² = 6381783994912722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 56487981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56487989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4911 + ... + 11708.

It is an arithmetic number, because the mean of its divisors is an integer number (5185440).

Almost surely, 2^56487981 is an apocalyptic number.

It is an amenable number.

56487981 is a deficient number, since it is larger than the sum of its proper divisors (26479059).

56487981 is a wasteful number, since it uses less digits than its factorization.

56487981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16736.

The product of its digits is 483840, while the sum is 48.

The square root of 56487981 is about 7515.8486546763. The cubic root of 56487981 is about 383.6943028730.

The spelling of 56487981 in words is "fifty-six million, four hundred eighty-seven thousand, nine hundred eighty-one".