55358991 has 8 divisors (see below), whose sum is σ = 82013360. Its totient is φ = 36905976.

The previous prime is 55358983. The next prime is 55359001. The reversal of 55358991 is 19985355.

55358991 is a `hidden beast` number, since 553 + 5 + 8 + 9 + 91 = 666.

It is not a de Polignac number, because 55358991 - 2³ = 55358983 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 (55358921) 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, 1025140 + ... + 1025193.

It is an arithmetic number, because the mean of its divisors is an integer number (10251670).

Almost surely, 2^55358991 is an apocalyptic number.

55358991 is a deficient number, since it is larger than the sum of its proper divisors (26654369).

55358991 is a wasteful number, since it uses less digits than its factorization.

55358991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2050342 (or 2050336 counting only the distinct ones).

The product of its digits is 243000, while the sum is 45.

The square root of 55358991 is about 7440.3622895663. The cubic root of 55358991 is about 381.1208618976.

The spelling of 55358991 in words is "fifty-five million, three hundred fifty-eight thousand, nine hundred ninety-one".