23531047921 has 2 divisors, whose sum is σ = 23531047922. Its totient is φ = 23531047920.

The previous prime is 23531047901. The next prime is 23531047927. The reversal of 23531047921 is 12974013532.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22560040000 + 971007921 = 150200^2 + 31161^2 .

It is a cyclic number.

It is not a de Polignac number, because 23531047921 - 2⁹ = 23531047409 is a prime.

It is not a weakly prime, because it can be changed into another prime (23531047927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11765523960 + 11765523961.

It is an arithmetic number, because the mean of its divisors is an integer number (11765523961).

Almost surely, 2^23531047921 is an apocalyptic number.

It is an amenable number.

23531047921 is a deficient number, since it is larger than the sum of its proper divisors (1).

23531047921 is an equidigital number, since it uses as much as digits as its factorization.

23531047921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 37.

The spelling of 23531047921 in words is "twenty-three billion, five hundred thirty-one million, forty-seven thousand, nine hundred twenty-one".