56665878 has 16 divisors (see below), whose sum is σ = 113525760. Its totient is φ = 18856296.

The previous prime is 56665877. The next prime is 56665891. The reversal of 56665878 is 87856665.

It is a super-2 number, since 2×56665878² = 6422043459021768, 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 56665878.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56665871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4138 + ... + 11421.

It is an arithmetic number, because the mean of its divisors is an integer number (7095360).

Almost surely, 2^56665878 is an apocalyptic number.

56665878 is an abundant number, since it is smaller than the sum of its proper divisors (56859882).

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

56665878 is a wasteful number, since it uses less digits than its factorization.

56665878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16171.

The product of its digits is 2419200, while the sum is 51.

The square root of 56665878 is about 7527.6741427881. The cubic root of 56665878 is about 384.0966689132.

The spelling of 56665878 in words is "fifty-six million, six hundred sixty-five thousand, eight hundred seventy-eight".