18682643640 has 64 divisors (see below), whose sum is σ = 56757427200. Its totient is φ = 4918972032.

The previous prime is 18682643549. The next prime is 18682643641. The reversal of 18682643640 is 4634628681.

It is a self number, because there is not a number n which added to its sum of digits gives 18682643640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18682643641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 975892 + ... + 994851.

It is an arithmetic number, because the mean of its divisors is an integer number (886834800).

Almost surely, 2^18682643640 is an apocalyptic number.

18682643640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18682643640 is an abundant number, since it is smaller than the sum of its proper divisors (38074783560).

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

18682643640 is a wasteful number, since it uses less digits than its factorization.

18682643640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1970836 (or 1970832 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 48.

The spelling of 18682643640 in words is "eighteen billion, six hundred eighty-two million, six hundred forty-three thousand, six hundred forty".