251240663123 has 2 divisors, whose sum is σ = 251240663124. Its totient is φ = 251240663122.

The previous prime is 251240663083. The next prime is 251240663159. The reversal of 251240663123 is 321366042152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 251240663123 - 2¹² = 251240659027 is a prime.

It is a super-2 number, since 2×251240663123² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (251240663423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125620331561 + 125620331562.

It is an arithmetic number, because the mean of its divisors is an integer number (125620331562).

Almost surely, 2^251240663123 is an apocalyptic number.

251240663123 is a deficient number, since it is larger than the sum of its proper divisors (1).

251240663123 is an equidigital number, since it uses as much as digits as its factorization.

251240663123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 35.

The spelling of 251240663123 in words is "two hundred fifty-one billion, two hundred forty million, six hundred sixty-three thousand, one hundred twenty-three".