21123131213227 has 2 divisors, whose sum is σ = 21123131213228. Its totient is φ = 21123131213226.

The previous prime is 21123131213203. The next prime is 21123131213243. The reversal of 21123131213227 is 72231213132112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21123131213227 - 2²³ = 21123122824619 is a prime.

It is not a weakly prime, because it can be changed into another prime (21123131273227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561565606613 + 10561565606614.

It is an arithmetic number, because the mean of its divisors is an integer number (10561565606614).

Almost surely, 2^{21123131213227} is an apocalyptic number.

21123131213227 is a deficient number, since it is larger than the sum of its proper divisors (1).

21123131213227 is an equidigital number, since it uses as much as digits as its factorization.

21123131213227 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 31.

Adding to 21123131213227 its reverse (72231213132112), we get a palindrome (93354344345339).

The spelling of 21123131213227 in words is "twenty-one trillion, one hundred twenty-three billion, one hundred thirty-one million, two hundred thirteen thousand, two hundred twenty-seven".