18397272057 has 4 divisors (see below), whose sum is σ = 24529696080. Its totient is φ = 12264848036.

The previous prime is 18397272043. The next prime is 18397272067. The reversal of 18397272057 is 75027279381.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18397272057 - 2⁷ = 18397271929 is a prime.

It is a super-2 number, since 2×18397272057² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18397272067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3066212007 + ... + 3066212012.

It is an arithmetic number, because the mean of its divisors is an integer number (6132424020).

Almost surely, 2^18397272057 is an apocalyptic number.

It is an amenable number.

18397272057 is a deficient number, since it is larger than the sum of its proper divisors (6132424023).

18397272057 is an equidigital number, since it uses as much as digits as its factorization.

18397272057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6132424022.

The product of its (nonzero) digits is 1481760, while the sum is 51.

The spelling of 18397272057 in words is "eighteen billion, three hundred ninety-seven million, two hundred seventy-two thousand, fifty-seven".