55555531 has 2 divisors, whose sum is σ = 55555532. Its totient is φ = 55555530.

The previous prime is 55555523. The next prime is 55555543. The reversal of 55555531 is 13555555.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 55555531 - 2³ = 55555523 is a prime.

It is a super-2 number, since 2×55555531² = 6172834049383922, which contains 22 as substring.

It is a nialpdrome in base 10.

It is not a weakly prime, because it can be changed into another prime (55555231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27777765 + 27777766.

It is an arithmetic number, because the mean of its divisors is an integer number (27777766).

Almost surely, 2^55555531 is an apocalyptic number.

55555531 is a deficient number, since it is larger than the sum of its proper divisors (1).

55555531 is an equidigital number, since it uses as much as digits as its factorization.

55555531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46875, while the sum is 34.

The square root of 55555531 is about 7453.5582777624. The cubic root of 55555531 is about 381.5713579662.

The spelling of 55555531 in words is "fifty-five million, five hundred fifty-five thousand, five hundred thirty-one".