55189391 has 4 divisors (see below), whose sum is σ = 55212192. Its totient is φ = 55166592.

The previous prime is 55189363. The next prime is 55189399. The reversal of 55189391 is 19398155.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55189391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55189399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7271 + ... + 12776.

It is an arithmetic number, because the mean of its divisors is an integer number (13803048).

Almost surely, 2^55189391 is an apocalyptic number.

55189391 is a deficient number, since it is larger than the sum of its proper divisors (22801).

55189391 is a wasteful number, since it uses less digits than its factorization.

55189391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22800.

The product of its digits is 48600, while the sum is 41.

The square root of 55189391 is about 7428.9562523951. The cubic root of 55189391 is about 380.7312580960.

The spelling of 55189391 in words is "fifty-five million, one hundred eighty-nine thousand, three hundred ninety-one".