18451589520 has 320 divisors, whose sum is σ = 70835466240. Its totient is φ = 3869005824.

The previous prime is 18451589477. The next prime is 18451589579. The reversal of 18451589520 is 2598515481.

It is a super-2 number, since 2×18451589520² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 18451589520.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3644751 + ... + 3649809.

It is an arithmetic number, because the mean of its divisors is an integer number (221360832).

Almost surely, 2^18451589520 is an apocalyptic number.

18451589520 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 18451589520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35417733120).

18451589520 is an abundant number, since it is smaller than the sum of its proper divisors (52383876720).

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

18451589520 is a wasteful number, since it uses less digits than its factorization.

18451589520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5262 (or 5256 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 48.

The spelling of 18451589520 in words is "eighteen billion, four hundred fifty-one million, five hundred eighty-nine thousand, five hundred twenty".