55543231 has 2 divisors, whose sum is σ = 55543232. Its totient is φ = 55543230.

The previous prime is 55543219. The next prime is 55543247. The reversal of 55543231 is 13234555.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55543231 is a prime.

It is a super-2 number, since 2×55543231² = 6170101019838722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55543231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55543211) 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, 27771615 + 27771616.

It is an arithmetic number, because the mean of its divisors is an integer number (27771616).

Almost surely, 2^55543231 is an apocalyptic number.

55543231 is a deficient number, since it is larger than the sum of its proper divisors (1).

55543231 is an equidigital number, since it uses as much as digits as its factorization.

55543231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9000, while the sum is 28.

The square root of 55543231 is about 7452.7331228215. The cubic root of 55543231 is about 381.5431959091.

Adding to 55543231 its reverse (13234555), we get a palindrome (68777786).

The spelling of 55543231 in words is "fifty-five million, five hundred forty-three thousand, two hundred thirty-one".