18987872715 has 64 divisors (see below), whose sum is σ = 38598067200. Its totient is φ = 8675776512.

The previous prime is 18987872689. The next prime is 18987872719. The reversal of 18987872715 is 51727878981.

It is not a de Polignac number, because 18987872715 - 2¹² = 18987868619 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (18987872719) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2531691 + ... + 2539179.

It is an arithmetic number, because the mean of its divisors is an integer number (603094800).

Almost surely, 2^18987872715 is an apocalyptic number.

18987872715 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18987872715 is an abundant number, since it is smaller than the sum of its proper divisors (19610194485).

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

18987872715 is a wasteful number, since it uses less digits than its factorization.

18987872715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10193 (or 10187 counting only the distinct ones).

The product of its digits is 15805440, while the sum is 63.

The spelling of 18987872715 in words is "eighteen billion, nine hundred eighty-seven million, eight hundred seventy-two thousand, seven hundred fifteen".