55220891 has 12 divisors (see below), whose sum is σ = 62183352. Its totient is φ = 48972000.

The previous prime is 55220887. The next prime is 55220899. The reversal of 55220891 is 19802255.

It is not a de Polignac number, because 55220891 - 2² = 55220887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55220899) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 605 + ... + 10526.

It is an arithmetic number, because the mean of its divisors is an integer number (5181946).

Almost surely, 2^55220891 is an apocalyptic number.

55220891 is a deficient number, since it is larger than the sum of its proper divisors (6962461).

55220891 is a wasteful number, since it uses less digits than its factorization.

55220891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11194 (or 11183 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 55220891 is about 7431.0760324464. The cubic root of 55220891 is about 380.8036799475.

The spelling of 55220891 in words is "fifty-five million, two hundred twenty thousand, eight hundred ninety-one".