21202220231 has 2 divisors, whose sum is σ = 21202220232. Its totient is φ = 21202220230.

The previous prime is 21202220219. The next prime is 21202220233. The reversal of 21202220231 is 13202220212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202220231 is a prime.

It is a super-2 number, since 2×21202220231² (a number of 21 digits) contains 22 as substring.

Together with 21202220233, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202220233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601110115 + 10601110116.

It is an arithmetic number, because the mean of its divisors is an integer number (10601110116).

Almost surely, 2^21202220231 is an apocalyptic number.

21202220231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202220231 is an equidigital number, since it uses as much as digits as its factorization.

21202220231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21202220231 its reverse (13202220212), we get a palindrome (34404440443).

The spelling of 21202220231 in words is "twenty-one billion, two hundred two million, two hundred twenty thousand, two hundred thirty-one".