18397872 has 30 divisors (see below), whose sum is σ = 51488892. Its totient is φ = 6132576.

The previous prime is 18397853. The next prime is 18397877. The reversal of 18397872 is 27879381.

It is not an unprimeable number, because it can be changed into a prime (18397877) 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 5 ways as a sum of consecutive naturals, for example, 63738 + ... + 64025.

Almost surely, 2^18397872 is an apocalyptic number.

18397872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18397872 is an abundant number, since it is smaller than the sum of its proper divisors (33091020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18397872 is a wasteful number, since it uses less digits than its factorization.

18397872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127777 (or 127768 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The square root of 18397872 is about 4289.2740644543. The cubic root of 18397872 is about 263.9910465283.

The spelling of 18397872 in words is "eighteen million, three hundred ninety-seven thousand, eight hundred seventy-two".