21122013431 has 2 divisors, whose sum is σ = 21122013432. Its totient is φ = 21122013430.

The previous prime is 21122013403. The next prime is 21122013487. The reversal of 21122013431 is 13431022112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21122013431 - 2³⁴ = 3942144247 is a prime.

It is a super-2 number, since 2×21122013431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21122013631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561006715 + 10561006716.

It is an arithmetic number, because the mean of its divisors is an integer number (10561006716).

Almost surely, 2^21122013431 is an apocalyptic number.

21122013431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122013431 is an equidigital number, since it uses as much as digits as its factorization.

21122013431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21122013431 its reverse (13431022112), we get a palindrome (34553035543).

The spelling of 21122013431 in words is "twenty-one billion, one hundred twenty-two million, thirteen thousand, four hundred thirty-one".