18987520000 has 130 divisors (see below), whose sum is σ = 47454214478. Its totient is φ = 7593984000.

The previous prime is 18987519977. The next prime is 18987520033. The reversal of 18987520000 is 2578981.

It can be written as a sum of positive squares in 5 ways, for example, as 4464377856 + 14523142144 = 66816^2 + 120512^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 2556292 + ... + 2563708.

Almost surely, 2^18987520000 is an apocalyptic number.

18987520000 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 18987520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23727107239).

18987520000 is an abundant number, since it is smaller than the sum of its proper divisors (28466694478).

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

18987520000 is an frugal number, since it uses more digits than its factorization.

18987520000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7461 (or 7424 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The spelling of 18987520000 in words is "eighteen billion, nine hundred eighty-seven million, five hundred twenty thousand".