21692725691 has 32 divisors (see below), whose sum is σ = 26873159040. Its totient is φ = 17051710464.

The previous prime is 21692725669. The next prime is 21692725697. The reversal of 21692725691 is 19652729612.

It is a cyclic number.

It is not a de Polignac number, because 21692725691 - 2⁶ = 21692725627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21692725697) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12996605 + ... + 12998273.

It is an arithmetic number, because the mean of its divisors is an integer number (839786220).

Almost surely, 2^21692725691 is an apocalyptic number.

21692725691 is a deficient number, since it is larger than the sum of its proper divisors (5180433349).

21692725691 is a wasteful number, since it uses less digits than its factorization.

21692725691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2535.

The product of its digits is 816480, while the sum is 50.

The spelling of 21692725691 in words is "twenty-one billion, six hundred ninety-two million, seven hundred twenty-five thousand, six hundred ninety-one".