21113231423 has 2 divisors, whose sum is σ = 21113231424. Its totient is φ = 21113231422.

The previous prime is 21113231407. The next prime is 21113231429. The reversal of 21113231423 is 32413231112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21113231423 - 2⁴ = 21113231407 is a prime.

It is a super-2 number, since 2×21113231423² (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 (21113231429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556615711 + 10556615712.

It is an arithmetic number, because the mean of its divisors is an integer number (10556615712).

Almost surely, 2^21113231423 is an apocalyptic number.

21113231423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113231423 is an equidigital number, since it uses as much as digits as its factorization.

21113231423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

Adding to 21113231423 its reverse (32413231112), we get a palindrome (53526462535).

The spelling of 21113231423 in words is "twenty-one billion, one hundred thirteen million, two hundred thirty-one thousand, four hundred twenty-three".