21220301231 has 2 divisors, whose sum is σ = 21220301232. Its totient is φ = 21220301230.

The previous prime is 21220301213. The next prime is 21220301233. The reversal of 21220301231 is 13210302212.

Together with previous prime (21220301213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21220301231 - 2¹⁰ = 21220300207 is a prime.

It is a super-2 number, since 2×21220301231² (a number of 21 digits) contains 22 as substring.

Together with 21220301233, 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 (21220301233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610150615 + 10610150616.

It is an arithmetic number, because the mean of its divisors is an integer number (10610150616).

Almost surely, 2^21220301231 is an apocalyptic number.

21220301231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220301231 is an equidigital number, since it uses as much as digits as its factorization.

21220301231 is an evil number, because the sum of its binary digits is even.

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

Adding to 21220301231 its reverse (13210302212), we get a palindrome (34430603443).

The spelling of 21220301231 in words is "twenty-one billion, two hundred twenty million, three hundred one thousand, two hundred thirty-one".