18215057 has 12 divisors (see below), whose sum is σ = 21766080. Its totient is φ = 14931048.

The previous prime is 18215051. The next prime is 18215059. The reversal of 18215057 is 75051281.

It is not a de Polignac number, because 18215057 - 2²⁴ = 1437841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18215051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1244 + ... + 6162.

It is an arithmetic number, because the mean of its divisors is an integer number (1813840).

Almost surely, 2^18215057 is an apocalyptic number.

It is an amenable number.

18215057 is a deficient number, since it is larger than the sum of its proper divisors (3551023).

18215057 is an equidigital number, since it uses as much as digits as its factorization.

18215057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4972 (or 4949 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 29.

The square root of 18215057 is about 4267.9101443212. The cubic root of 18215057 is about 263.1137301064.

The spelling of 18215057 in words is "eighteen million, two hundred fifteen thousand, fifty-seven".