55509931 has 2 divisors, whose sum is σ = 55509932. Its totient is φ = 55509930.

The previous prime is 55509919. The next prime is 55509977. The reversal of 55509931 is 13990555.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 55509931 - 2⁷ = 55509803 is a prime.

It is a super-2 number, since 2×55509931² = 6162704879249522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55509331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27754965 + 27754966.

It is an arithmetic number, because the mean of its divisors is an integer number (27754966).

Almost surely, 2^55509931 is an apocalyptic number.

55509931 is a deficient number, since it is larger than the sum of its proper divisors (1).

55509931 is an equidigital number, since it uses as much as digits as its factorization.

55509931 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30375, while the sum is 37.

The square root of 55509931 is about 7450.4987081403. The cubic root of 55509931 is about 381.4669314202.

The spelling of 55509931 in words is "fifty-five million, five hundred nine thousand, nine hundred thirty-one".