21131022231 has 64 divisors (see below), whose sum is σ = 36865152000. Its totient is φ = 11827347840.

The previous prime is 21131022229. The next prime is 21131022239. The reversal of 21131022231 is 13222013112.

It is not a de Polignac number, because 21131022231 - 2¹ = 21131022229 is a prime.

It is a super-2 number, since 2×21131022231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131022239) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 144765 + ... + 251433.

It is an arithmetic number, because the mean of its divisors is an integer number (576018000).

Almost surely, 2^21131022231 is an apocalyptic number.

21131022231 is a deficient number, since it is larger than the sum of its proper divisors (15734129769).

21131022231 is a wasteful number, since it uses less digits than its factorization.

21131022231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106741 (or 106735 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21131022231 its reverse (13222013112), we get a palindrome (34353035343).

The spelling of 21131022231 in words is "twenty-one billion, one hundred thirty-one million, twenty-two thousand, two hundred thirty-one".