18998980 has 144 divisors (see below), whose sum is σ = 54601344. Its totient is φ = 5391360.

The previous prime is 18998977. The next prime is 18998981. The reversal of 18998980 is 8989981.

It is a super-2 number, since 2×18998980² = 721922482080800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (18998981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 260224 + ... + 260296.

It is an arithmetic number, because the mean of its divisors is an integer number (379176).

Almost surely, 2^18998980 is an apocalyptic number.

18998980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18998980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27300672).

18998980 is an abundant number, since it is smaller than the sum of its proper divisors (35602364).

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

18998980 is a wasteful number, since it uses less digits than its factorization.

18998980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 52.

The square root of 18998980 is about 4358.7819399461. The cubic root of 18998980 is about 266.8353897522.

The spelling of 18998980 in words is "eighteen million, nine hundred ninety-eight thousand, nine hundred eighty".