18539980 has 24 divisors (see below), whose sum is σ = 39096288. Its totient is φ = 7385088.

The previous prime is 18539977. The next prime is 18540007. The reversal of 18539980 is 8993581.

It is an unprimeable number.

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, 3337 + ... + 6943.

It is an arithmetic number, because the mean of its divisors is an integer number (1629012).

Almost surely, 2^18539980 is an apocalyptic number.

18539980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18539980 is an abundant number, since it is smaller than the sum of its proper divisors (20556308).

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

18539980 is a wasteful number, since it uses less digits than its factorization.

18539980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3873 (or 3871 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 18539980 is about 4305.8077058782. The cubic root of 18539980 is about 264.6690064729.

The spelling of 18539980 in words is "eighteen million, five hundred thirty-nine thousand, nine hundred eighty".