21319796169 has 81 divisors (see below), whose sum is σ = 38147522517. Its totient is φ = 11438074368.

The previous prime is 21319796167. The next prime is 21319796209. The reversal of 21319796169 is 96169791312.

The square root of 21319796169 is 146013.

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

21319796169 is a `hidden beast` number, since 2 + 1 + 3 + 19 + 7 + 9 + 616 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 10610030025 + 10709766144 = 103005^2 + 103488^2 .

It is not a de Polignac number, because 21319796169 - 2¹ = 21319796167 is a prime.

It is a super-2 number, since 2×21319796169² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21319796167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 52126437 + ... + 52126845.

Almost surely, 2^21319796169 is an apocalyptic number.

21319796169 is the 146013-rd square number.

21319796169 is the 73007-th centered octagonal number.

It is an amenable number.

21319796169 is a deficient number, since it is larger than the sum of its proper divisors (16827726348).

21319796169 is an equidigital number, since it uses as much as digits as its factorization.

21319796169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 872 (or 436 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 54.

The spelling of 21319796169 in words is "twenty-one billion, three hundred nineteen million, seven hundred ninety-six thousand, one hundred sixty-nine".