55820215 has 32 divisors (see below), whose sum is σ = 76723200. Its totient is φ = 38613120.

The previous prime is 55820207. The next prime is 55820227. The reversal of 55820215 is 51202855.

It is not a de Polignac number, because 55820215 - 2³ = 55820207 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125784 + ... + 126226.

It is an arithmetic number, because the mean of its divisors is an integer number (2397600).

Almost surely, 2^55820215 is an apocalyptic number.

55820215 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

55820215 is a deficient number, since it is larger than the sum of its proper divisors (20902985).

55820215 is a wasteful number, since it uses less digits than its factorization.

55820215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 567.

The product of its (nonzero) digits is 4000, while the sum is 28.

The square root of 55820215 is about 7471.2927261619. The cubic root of 55820215 is about 382.1763734209.

The spelling of 55820215 in words is "fifty-five million, eight hundred twenty thousand, two hundred fifteen".