21023131312231 has 16 divisors (see below), whose sum is σ = 22206767109120. Its totient is φ = 19871121029760.

The previous prime is 21023131312159. The next prime is 21023131312237. The reversal of 21023131312231 is 13221313132012.

It is a cyclic number.

It is not a de Polignac number, because 21023131312231 - 2²¹ = 21023129215079 is a prime.

It is a super-2 number, since 2×21023131312231² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21023131312196 and 21023131312205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023131312237) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39355455 + ... + 39886063.

It is an arithmetic number, because the mean of its divisors is an integer number (1387922944320).

Almost surely, 2^{21023131312231} is an apocalyptic number.

21023131312231 is a deficient number, since it is larger than the sum of its proper divisors (1183635796889).

21023131312231 is a wasteful number, since it uses less digits than its factorization.

21023131312231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 560406.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 21023131312231 its reverse (13221313132012), we get a palindrome (34244444444243).

The spelling of 21023131312231 in words is "twenty-one trillion, twenty-three billion, one hundred thirty-one million, three hundred twelve thousand, two hundred thirty-one".