21522223531 has 4 divisors (see below), whose sum is σ = 22264369200. Its totient is φ = 20780077864.

The previous prime is 21522223519. The next prime is 21522223537. The reversal of 21522223531 is 13532222512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21522223531 is a prime.

It is a super-2 number, since 2×21522223531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21522223531.

It is not an unprimeable number, because it can be changed into a prime (21522223537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 371072791 + ... + 371072848.

It is an arithmetic number, because the mean of its divisors is an integer number (5566092300).

Almost surely, 2^21522223531 is an apocalyptic number.

21522223531 is a deficient number, since it is larger than the sum of its proper divisors (742145669).

21522223531 is an equidigital number, since it uses as much as digits as its factorization.

21522223531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742145668.

The product of its digits is 7200, while the sum is 28.

The spelling of 21522223531 in words is "twenty-one billion, five hundred twenty-two million, two hundred twenty-three thousand, five hundred thirty-one".