18787980 has 24 divisors (see below), whose sum is σ = 52606512. Its totient is φ = 5010112.

The previous prime is 18787943. The next prime is 18787991. The reversal of 18787980 is 8978781.

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, 156507 + ... + 156626.

It is an arithmetic number, because the mean of its divisors is an integer number (2191938).

Almost surely, 2^18787980 is an apocalyptic number.

18787980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18787980 is an abundant number, since it is smaller than the sum of its proper divisors (33818532).

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

18787980 is a wasteful number, since it uses less digits than its factorization.

18787980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313145 (or 313143 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 48.

The square root of 18787980 is about 4334.5103529695. The cubic root of 18787980 is about 265.8438980830.

The spelling of 18787980 in words is "eighteen million, seven hundred eighty-seven thousand, nine hundred eighty".