18718784667648 has 1200 divisors, whose sum is σ = 62106005586240. Its totient is φ = 5583264546816.

The previous prime is 18718784667637. The next prime is 18718784667679. The reversal of 18718784667648 is 84676648781781.

18718784667648 is a `hidden beast` number, since 1 + 8 + 7 + 1 + 87 + 8 + 466 + 76 + 4 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 112088530861 + ... + 112088531027.

Almost surely, 2^{18718784667648} is an apocalyptic number.

18718784667648 is a gapful number since it is divisible by the number (18) 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 18718784667648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31053002793120).

18718784667648 is an abundant number, since it is smaller than the sum of its proper divisors (43387220918592).

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

18718784667648 is an equidigital number, since it uses as much as digits as its factorization.

18718784667648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 347 counting only the distinct ones).

The product of its digits is 4855431168, while the sum is 81.

The spelling of 18718784667648 in words is "eighteen trillion, seven hundred eighteen billion, seven hundred eighty-four million, six hundred sixty-seven thousand, six hundred forty-eight".