18712787856 has 160 divisors (see below), whose sum is σ = 58211512320. Its totient is φ = 5064187392.

The previous prime is 18712787843. The next prime is 18712787861. The reversal of 18712787856 is 65878721781.

It is a super-2 number, since 2×18712787856² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18712787856.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 784230 + ... + 807738.

It is an arithmetic number, because the mean of its divisors is an integer number (363821952).

Almost surely, 2^18712787856 is an apocalyptic number.

18712787856 is a gapful number since it is divisible by the number (16) 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 18712787856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29105756160).

18712787856 is an abundant number, since it is smaller than the sum of its proper divisors (39498724464).

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

18712787856 is a wasteful number, since it uses less digits than its factorization.

18712787856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23653 (or 23647 counting only the distinct ones).

The product of its digits is 10536960, while the sum is 60.

The spelling of 18712787856 in words is "eighteen billion, seven hundred twelve million, seven hundred eighty-seven thousand, eight hundred fifty-six".