20189816664 has 32 divisors (see below), whose sum is σ = 50512657920. Its totient is φ = 6724856736.

The previous prime is 20189816639. The next prime is 20189816681. The reversal of 20189816664 is 46661898102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 285124 + ... + 348819.

It is an arithmetic number, because the mean of its divisors is an integer number (1578520560).

Almost surely, 2^20189816664 is an apocalyptic number.

20189816664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20189816664 is an abundant number, since it is smaller than the sum of its proper divisors (30322841256).

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

20189816664 is a wasteful number, since it uses less digits than its factorization.

20189816664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635279 (or 635275 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 51.

The spelling of 20189816664 in words is "twenty billion, one hundred eighty-nine million, eight hundred sixteen thousand, six hundred sixty-four".