18351980 has 24 divisors (see below), whose sum is σ = 38646720. Its totient is φ = 7320320.

The previous prime is 18351961. The next prime is 18351989. The reversal of 18351980 is 8915381.

It is a self number, because there is not a number n which added to its sum of digits gives 18351980.

It is not an unprimeable number, because it can be changed into a prime (18351989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7556 + ... + 9684.

It is an arithmetic number, because the mean of its divisors is an integer number (1610280).

Almost surely, 2^18351980 is an apocalyptic number.

18351980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18351980 is an abundant number, since it is smaller than the sum of its proper divisors (20294740).

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

18351980 is a wasteful number, since it uses less digits than its factorization.

18351980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2569 (or 2567 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 18351980 is about 4283.9211010475. The cubic root of 18351980 is about 263.7713623451.

The spelling of 18351980 in words is "eighteen million, three hundred fifty-one thousand, nine hundred eighty".