18539972 has 48 divisors (see below), whose sum is σ = 37927680. Its totient is φ = 7840800.

The previous prime is 18539971. The next prime is 18539977. The reversal of 18539972 is 27993581.

It is a Harshad number since it is a multiple of its sum of digits (44).

18539972 is a Rhonda number in base 12.

Its product of digits (136080) is a multiple of the sum of its prime factors (432).

It is not an unprimeable number, because it can be changed into a prime (18539971) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55847 + ... + 56177.

It is an arithmetic number, because the mean of its divisors is an integer number (790160).

Almost surely, 2^18539972 is an apocalyptic number.

It is an amenable number.

18539972 is an abundant number, since it is smaller than the sum of its proper divisors (19387708).

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

18539972 is a wasteful number, since it uses less digits than its factorization.

18539972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432 (or 430 counting only the distinct ones).

The product of its digits is 136080, while the sum is 44.

The square root of 18539972 is about 4305.8067769002. The cubic root of 18539972 is about 264.6689684047.

The spelling of 18539972 in words is "eighteen million, five hundred thirty-nine thousand, nine hundred seventy-two".