18918980 has 12 divisors (see below), whose sum is σ = 39729900. Its totient is φ = 7567584.

The previous prime is 18918973. The next prime is 18918983. The reversal of 18918980 is 8981981.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 5317636 + 13601344 = 2306^2 + 3688^2 .

It is not an unprimeable number, because it can be changed into a prime (18918983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 472955 + ... + 472994.

It is an arithmetic number, because the mean of its divisors is an integer number (3310825).

Almost surely, 2^18918980 is an apocalyptic number.

18918980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18918980 is an abundant number, since it is smaller than the sum of its proper divisors (20810920).

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

18918980 is a wasteful number, since it uses less digits than its factorization.

18918980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 945958 (or 945956 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 44.

The square root of 18918980 is about 4349.5953834811. The cubic root of 18918980 is about 266.4603369241.

The spelling of 18918980 in words is "eighteen million, nine hundred eighteen thousand, nine hundred eighty".