231304128421 has 2 divisors, whose sum is σ = 231304128422. Its totient is φ = 231304128420.

The previous prime is 231304128403. The next prime is 231304128437. The reversal of 231304128421 is 124821403132.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 218453412100 + 12850716321 = 467390^2 + 113361^2 .

It is a cyclic number.

It is not a de Polignac number, because 231304128421 - 2²¹ = 231302031269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231394128421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115652064210 + 115652064211.

It is an arithmetic number, because the mean of its divisors is an integer number (115652064211).

Almost surely, 2^231304128421 is an apocalyptic number.

It is an amenable number.

231304128421 is a deficient number, since it is larger than the sum of its proper divisors (1).

231304128421 is an equidigital number, since it uses as much as digits as its factorization.

231304128421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 31.

The spelling of 231304128421 in words is "two hundred thirty-one billion, three hundred four million, one hundred twenty-eight thousand, four hundred twenty-one".