55918590 has 64 divisors (see below), whose sum is σ = 165182976. Its totient is φ = 11797632.

The previous prime is 55918573. The next prime is 55918609. The reversal of 55918590 is 9581955.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

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 31 ways as a sum of consecutive naturals, for example, 7512 + ... + 12971.

It is an arithmetic number, because the mean of its divisors is an integer number (2580984).

Almost surely, 2^55918590 is an apocalyptic number.

55918590 is an abundant number, since it is smaller than the sum of its proper divisors (109264386).

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

55918590 is a wasteful number, since it uses less digits than its factorization.

55918590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20513.

The product of its (nonzero) digits is 81000, while the sum is 42.

The square root of 55918590 is about 7477.8733607891. The cubic root of 55918590 is about 382.4007517288.

The spelling of 55918590 in words is "fifty-five million, nine hundred eighteen thousand, five hundred ninety".