55213831 has 2 divisors, whose sum is σ = 55213832. Its totient is φ = 55213830.

The previous prime is 55213801. The next prime is 55213843. The reversal of 55213831 is 13831255.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55213831 - 2⁷ = 55213703 is a prime.

It is a super-2 number, since 2×55213831² = 6097134267393122, 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 55213831.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55213801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27606915 + 27606916.

It is an arithmetic number, because the mean of its divisors is an integer number (27606916).

Almost surely, 2^55213831 is an apocalyptic number.

55213831 is a deficient number, since it is larger than the sum of its proper divisors (1).

55213831 is an equidigital number, since it uses as much as digits as its factorization.

55213831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3600, while the sum is 28.

The square root of 55213831 is about 7430.6009851155. The cubic root of 55213831 is about 380.7874506514.

The spelling of 55213831 in words is "fifty-five million, two hundred thirteen thousand, eight hundred thirty-one".