20804312169 has 9 divisors (see below), whose sum is σ = 30051298173. Its totient is φ = 13869252972.

The previous prime is 20804312149. The next prime is 20804312183. The reversal of 20804312169 is 96121340802.

The square root of 20804312169 is 144237.

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

20804312169 is a `hidden beast` number, since 2 + 0 + 8 + 0 + 431 + 216 + 9 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 20804312169 - 2⁷ = 20804312041 is a prime.

It is a super-2 number, since 2×20804312169² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20804312119) 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, 408672 + ... + 456750.

Almost surely, 2^20804312169 is an apocalyptic number.

20804312169 is the 144237-th square number.

20804312169 is the 72119-th centered octagonal number.

It is an amenable number.

20804312169 is a deficient number, since it is larger than the sum of its proper divisors (9246986004).

20804312169 is an frugal number, since it uses more digits than its factorization.

20804312169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96164 (or 48082 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

Multiplying 20804312169 by its sum of digits (36), we get a square (748955238084 = 865422²).

Multiplying 20804312169 by its product of nonzero digits (20736), we get a square (431398217136384 = 20770128²).

The spelling of 20804312169 in words is "twenty billion, eight hundred four million, three hundred twelve thousand, one hundred sixty-nine".