18821570418 has 36 divisors (see below), whose sum is σ = 47438041950. Its totient is φ = 5377591296.

The previous prime is 18821570371. The next prime is 18821570477. The reversal of 18821570418 is 81407512881.

18821570418 is a `hidden beast` number, since 1 + 8 + 82 + 157 + 0 + 418 = 666.

It can be written as a sum of positive squares in only one way, i.e., 14871070809 + 3950499609 = 121947^2 + 62853^2 .

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 17 ways as a sum of consecutive naturals, for example, 10668943 + ... + 10670706.

Almost surely, 2^18821570418 is an apocalyptic number.

18821570418 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18821570418 is an abundant number, since it is smaller than the sum of its proper divisors (28616471532).

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

18821570418 is a wasteful number, since it uses less digits than its factorization.

18821570418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21339671 (or 21339661 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 45.

The spelling of 18821570418 in words is "eighteen billion, eight hundred twenty-one million, five hundred seventy thousand, four hundred eighteen".