18939705563772 has 384 divisors, whose sum is σ = 58725935923200. Its totient is φ = 5165721153792.

The previous prime is 18939705563719. The next prime is 18939705563791. The reversal of 18939705563772 is 27736550793981.

18939705563772 is a `hidden beast` number, since 1 + 8 + 9 + 39 + 7 + 0 + 556 + 37 + 7 + 2 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 18939705563772.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 863121033 + ... + 863142975.

It is an arithmetic number, because the mean of its divisors is an integer number (152932124800).

Almost surely, 2^{18939705563772} is an apocalyptic number.

18939705563772 is a gapful number since it is divisible by the number (12) 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 18939705563772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29362967961600).

18939705563772 is an abundant number, since it is smaller than the sum of its proper divisors (39786230359428).

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

18939705563772 is a wasteful number, since it uses less digits than its factorization.

18939705563772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22582 (or 22574 counting only the distinct ones).

The product of its (nonzero) digits is 600112800, while the sum is 72.

The spelling of 18939705563772 in words is "eighteen trillion, nine hundred thirty-nine billion, seven hundred five million, five hundred sixty-three thousand, seven hundred seventy-two".