21659897435231 has 32 divisors (see below), whose sum is σ = 25007451356160. Its totient is φ = 18566554406400.

The previous prime is 21659897435201. The next prime is 21659897435233. The reversal of 21659897435231 is 13253479895612.

It is not a de Polignac number, because 21659897435231 - 2¹⁰ = 21659897434207 is a prime.

It is a super-2 number, since 2×21659897435231² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21659897435233) 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, 120855335 + ... + 121034423.

It is an arithmetic number, because the mean of its divisors is an integer number (781482854880).

Almost surely, 2^{21659897435231} is an apocalyptic number.

21659897435231 is a deficient number, since it is larger than the sum of its proper divisors (3347553920929).

21659897435231 is a wasteful number, since it uses less digits than its factorization.

21659897435231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185927.

The product of its digits is 97977600, while the sum is 65.

The spelling of 21659897435231 in words is "twenty-one trillion, six hundred fifty-nine billion, eight hundred ninety-seven million, four hundred thirty-five thousand, two hundred thirty-one".