21100628105764 has 45 divisors (see below), whose sum is σ = 38258895691191. Its totient is φ = 10182780163920.

The previous prime is 21100628105741. The next prime is 21100628105789. The reversal of 21100628105764 is 46750182600112.

The square root of 21100628105764 is 4593542.

It is a perfect power (a square), and thus also a powerful number.

21100628105764 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 50150019364 + 21050478086400 = 223942^2 + 4588080^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21100628105764.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 7726336279 + ... + 7726339009.

Almost surely, 2^{21100628105764} is an apocalyptic number.

21100628105764 is the 4593542-nd square number.

It is an amenable number.

21100628105764 is a deficient number, since it is larger than the sum of its proper divisors (17158267585427).

21100628105764 is an frugal number, since it uses more digits than its factorization.

21100628105764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5582 (or 2762 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 43.

The spelling of 21100628105764 in words is "twenty-one trillion, one hundred billion, six hundred twenty-eight million, one hundred five thousand, seven hundred sixty-four".