55778631 has 8 divisors (see below), whose sum is σ = 75774960. Its totient is φ = 36484032.

The previous prime is 55778617. The next prime is 55778633. The reversal of 55778631 is 13687755.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 55778631 - 2⁵ = 55778599 is a prime.

It is a super-2 number, since 2×55778631² = 6222511352468322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55778633) 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, 175246 + ... + 175563.

It is an arithmetic number, because the mean of its divisors is an integer number (9471870).

Almost surely, 2^55778631 is an apocalyptic number.

55778631 is the 4724-th centered pentagonal number.

55778631 is a deficient number, since it is larger than the sum of its proper divisors (19996329).

55778631 is a wasteful number, since it uses less digits than its factorization.

55778631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350865.

The product of its digits is 176400, while the sum is 42.

The square root of 55778631 is about 7468.5092890081. The cubic root of 55778631 is about 382.0814474139.

The spelling of 55778631 in words is "fifty-five million, seven hundred seventy-eight thousand, six hundred thirty-one".