18099980 has 12 divisors (see below), whose sum is σ = 38010000. Its totient is φ = 7239984.

The previous prime is 18099971. The next prime is 18099997. The reversal of 18099980 is 8999081.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 452480 + ... + 452519.

It is an arithmetic number, because the mean of its divisors is an integer number (3167500).

Almost surely, 2^18099980 is an apocalyptic number.

18099980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18099980 is an abundant number, since it is smaller than the sum of its proper divisors (19910020).

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

18099980 is a wasteful number, since it uses less digits than its factorization.

18099980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905008 (or 905006 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 44.

The square root of 18099980 is about 4254.4071267334. The cubic root of 18099980 is about 262.5584692129.

The spelling of 18099980 in words is "eighteen million, ninety-nine thousand, nine hundred eighty".