56639988 has 72 divisors (see below), whose sum is σ = 159606720. Its totient is φ = 16830720.

The previous prime is 56639981. The next prime is 56640011. The reversal of 56639988 is 88993665.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56639981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9193 + ... + 14063.

It is an arithmetic number, because the mean of its divisors is an integer number (2216760).

Almost surely, 2^56639988 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56639988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79803360).

56639988 is an abundant number, since it is smaller than the sum of its proper divisors (102966732).

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

56639988 is a wasteful number, since it uses less digits than its factorization.

56639988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4917 (or 4912 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 56639988 is about 7525.9542916497. The cubic root of 56639988 is about 384.0381635247.

It can be divided in two parts, 5663 and 9988, that added together give a palindrome (15651).

The spelling of 56639988 in words is "fifty-six million, six hundred thirty-nine thousand, nine hundred eighty-eight".