21323042431 has 2 divisors, whose sum is σ = 21323042432. Its totient is φ = 21323042430.

The previous prime is 21323042399. The next prime is 21323042459. The reversal of 21323042431 is 13424032312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21323042431 - 2⁵ = 21323042399 is a prime.

It is a super-2 number, since 2×21323042431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21323042396 and 21323042405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21323042471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661521215 + 10661521216.

It is an arithmetic number, because the mean of its divisors is an integer number (10661521216).

Almost surely, 2^21323042431 is an apocalyptic number.

21323042431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323042431 is an equidigital number, since it uses as much as digits as its factorization.

21323042431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21323042431 its reverse (13424032312), we get a palindrome (34747074743).

The spelling of 21323042431 in words is "twenty-one billion, three hundred twenty-three million, forty-two thousand, four hundred thirty-one".