21220023131 has 16 divisors (see below), whose sum is σ = 21763766880. Its totient is φ = 20683004160.

The previous prime is 21220023119. The next prime is 21220023151. The reversal of 21220023131 is 13132002212.

It is not a de Polignac number, because 21220023131 - 2¹⁸ = 21219760987 is a prime.

It is a super-2 number, since 2×21220023131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21220023151) 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, 4823825 + ... + 4828221.

It is an arithmetic number, because the mean of its divisors is an integer number (1360235430).

Almost surely, 2^21220023131 is an apocalyptic number.

21220023131 is a deficient number, since it is larger than the sum of its proper divisors (543743749).

21220023131 is a wasteful number, since it uses less digits than its factorization.

21220023131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5134.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21220023131 its reverse (13132002212), we get a palindrome (34352025343).

The spelling of 21220023131 in words is "twenty-one billion, two hundred twenty million, twenty-three thousand, one hundred thirty-one".