231618265421 has 2 divisors, whose sum is σ = 231618265422. Its totient is φ = 231618265420.

The previous prime is 231618265337. The next prime is 231618265429. The reversal of 231618265421 is 124562816132.

231618265421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 226589328196 + 5028937225 = 476014^2 + 70915^2 .

It is a cyclic number.

It is not a de Polignac number, because 231618265421 - 2¹⁸ = 231618003277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231618265429) 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, 115809132710 + 115809132711.

It is an arithmetic number, because the mean of its divisors is an integer number (115809132711).

Almost surely, 2^231618265421 is an apocalyptic number.

It is an amenable number.

231618265421 is a deficient number, since it is larger than the sum of its proper divisors (1).

231618265421 is an equidigital number, since it uses as much as digits as its factorization.

231618265421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 138240, while the sum is 41.

The spelling of 231618265421 in words is "two hundred thirty-one billion, six hundred eighteen million, two hundred sixty-five thousand, four hundred twenty-one".