18918558720 has 352 divisors, whose sum is σ = 67914547200. Its totient is φ = 4993892352.

The previous prime is 18918558707. The next prime is 18918558739. The reversal of 18918558720 is 2785581981.

18918558720 is a `hidden beast` number, since 1 + 8 + 9 + 18 + 558 + 72 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14791041 + ... + 14792319.

Almost surely, 2^18918558720 is an apocalyptic number.

18918558720 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 18918558720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33957273600).

18918558720 is an abundant number, since it is smaller than the sum of its proper divisors (48995988480).

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

18918558720 is a wasteful number, since it uses less digits than its factorization.

18918558720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420 (or 1396 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 54.

The spelling of 18918558720 in words is "eighteen billion, nine hundred eighteen million, five hundred fifty-eight thousand, seven hundred twenty".