55331815 has 16 divisors (see below), whose sum is σ = 82782720. Its totient is φ = 34492320.

The previous prime is 55331803. The next prime is 55331851. The reversal of 55331815 is 51813355.

It is not a de Polignac number, because 55331815 - 2⁹ = 55331303 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71475 + ... + 72244.

It is an arithmetic number, because the mean of its divisors is an integer number (5173920).

Almost surely, 2^55331815 is an apocalyptic number.

55331815 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

55331815 is a deficient number, since it is larger than the sum of its proper divisors (27450905).

55331815 is a wasteful number, since it uses less digits than its factorization.

55331815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143742.

The product of its digits is 9000, while the sum is 31.

The square root of 55331815 is about 7438.5358102250. The cubic root of 55331815 is about 381.0584869901.

The spelling of 55331815 in words is "fifty-five million, three hundred thirty-one thousand, eight hundred fifteen".