21113241431 has 2 divisors, whose sum is σ = 21113241432. Its totient is φ = 21113241430.

The previous prime is 21113241349. The next prime is 21113241433. The reversal of 21113241431 is 13414231112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113241431 is a prime.

It is a super-2 number, since 2×21113241431² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 21113241433, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21113241397 and 21113241406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21113241433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556620715 + 10556620716.

It is an arithmetic number, because the mean of its divisors is an integer number (10556620716).

Almost surely, 2^21113241431 is an apocalyptic number.

21113241431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113241431 is an equidigital number, since it uses as much as digits as its factorization.

21113241431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

Adding to 21113241431 its reverse (13414231112), we get a palindrome (34527472543).

The spelling of 21113241431 in words is "twenty-one billion, one hundred thirteen million, two hundred forty-one thousand, four hundred thirty-one".