251687697113 has 2 divisors, whose sum is σ = 251687697114. Its totient is φ = 251687697112.

The previous prime is 251687697083. The next prime is 251687697133. The reversal of 251687697113 is 311796786152.

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., 251149317904 + 538379209 = 501148^2 + 23203^2 .

It is a cyclic number.

It is not a de Polignac number, because 251687697113 - 2⁶ = 251687697049 is a prime.

It is not a weakly prime, because it can be changed into another prime (251687697133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125843848556 + 125843848557.

It is an arithmetic number, because the mean of its divisors is an integer number (125843848557).

Almost surely, 2^251687697113 is an apocalyptic number.

It is an amenable number.

251687697113 is a deficient number, since it is larger than the sum of its proper divisors (1).

251687697113 is an equidigital number, since it uses as much as digits as its factorization.

251687697113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3810240, while the sum is 56.

The spelling of 251687697113 in words is "two hundred fifty-one billion, six hundred eighty-seven million, six hundred ninety-seven thousand, one hundred thirteen".