21699777523204 has 27 divisors (see below), whose sum is σ = 41740884888213. Its totient is φ = 9863488654800.

The previous prime is 21699777523201. The next prime is 21699777523219. The reversal of 21699777523204 is 40232577799612.

The square root of 21699777523204 is 4658302.

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

It can be written as a sum of positive squares in only one way, i.e., 19455174283204 + 2244603240000 = 4410802^2 + 1498200^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21699777523201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 102376774 + ... + 102588514.

Almost surely, 2^{21699777523204} is an apocalyptic number.

21699777523204 is the 4658302-nd square number.

It is an amenable number.

21699777523204 is a deficient number, since it is larger than the sum of its proper divisors (20041107365009).

21699777523204 is an frugal number, since it uses more digits than its factorization.

21699777523204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423508 (or 211754 counting only the distinct ones).

The product of its (nonzero) digits is 80015040, while the sum is 64.

The spelling of 21699777523204 in words is "twenty-one trillion, six hundred ninety-nine billion, seven hundred seventy-seven million, five hundred twenty-three thousand, two hundred four".