21320430023 has 2 divisors, whose sum is σ = 21320430024. Its totient is φ = 21320430022.

The previous prime is 21320429993. The next prime is 21320430041. The reversal of 21320430023 is 32003402312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21320430023 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21320429977 and 21320430004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21320430073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660215011 + 10660215012.

It is an arithmetic number, because the mean of its divisors is an integer number (10660215012).

Almost surely, 2^21320430023 is an apocalyptic number.

21320430023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21320430023 is an equidigital number, since it uses as much as digits as its factorization.

21320430023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 20.

Adding to 21320430023 its reverse (32003402312), we get a palindrome (53323832335).

The spelling of 21320430023 in words is "twenty-one billion, three hundred twenty million, four hundred thirty thousand, twenty-three".