231551551023257 has 2 divisors, whose sum is σ = 231551551023258. Its totient is φ = 231551551023256.

The previous prime is 231551551023223. The next prime is 231551551023259. The reversal of 231551551023257 is 752320155155132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117029470176256 + 114522080847001 = 10818016^2 + 10701499^2 .

It is a cyclic number.

It is not a de Polignac number, because 231551551023257 - 2⁴⁴ = 213959364978841 is a prime.

It is a super-2 number, since 2×231551551023257² (a number of 30 digits) contains 22 as substring.

Together with 231551551023259, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (231551551023259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115775775511628 + 115775775511629.

It is an arithmetic number, because the mean of its divisors is an integer number (115775775511629).

Almost surely, 2^{231551551023257} is an apocalyptic number.

It is an amenable number.

231551551023257 is a deficient number, since it is larger than the sum of its proper divisors (1).

231551551023257 is an equidigital number, since it uses as much as digits as its factorization.

231551551023257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1575000, while the sum is 47.

The spelling of 231551551023257 in words is "two hundred thirty-one trillion, five hundred fifty-one billion, five hundred fifty-one million, twenty-three thousand, two hundred fifty-seven".