55512891 has 32 divisors (see below), whose sum is σ = 94348800. Its totient is φ = 31600800.

The previous prime is 55512883. The next prime is 55512901. The reversal of 55512891 is 19821555.

It is a happy number.

55512891 is a `hidden beast` number, since 55 + 512 + 8 + 91 = 666.

It is not a de Polignac number, because 55512891 - 2³ = 55512883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55532891) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78841 + ... + 79541.

It is an arithmetic number, because the mean of its divisors is an integer number (2948400).

Almost surely, 2^55512891 is an apocalyptic number.

55512891 is a deficient number, since it is larger than the sum of its proper divisors (38835909).

55512891 is a wasteful number, since it uses less digits than its factorization.

55512891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1136 (or 1130 counting only the distinct ones).

The product of its digits is 18000, while the sum is 36.

The square root of 55512891 is about 7450.6973499130. The cubic root of 55512891 is about 381.4737117208.

The spelling of 55512891 in words is "fifty-five million, five hundred twelve thousand, eight hundred ninety-one".