18331980 has 24 divisors (see below), whose sum is σ = 51329712. Its totient is φ = 4888512.

The previous prime is 18331969. The next prime is 18331981. The reversal of 18331980 is 8913381.

It is a super-2 number, since 2×18331980² = 672122981440800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18331981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152707 + ... + 152826.

It is an arithmetic number, because the mean of its divisors is an integer number (2138738).

Almost surely, 2^18331980 is an apocalyptic number.

18331980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18331980 is an abundant number, since it is smaller than the sum of its proper divisors (32997732).

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

18331980 is a wasteful number, since it uses less digits than its factorization.

18331980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305545 (or 305543 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 18331980 is about 4281.5861546861. The cubic root of 18331980 is about 263.6755081140.

The spelling of 18331980 in words is "eighteen million, three hundred thirty-one thousand, nine hundred eighty".