251255617 has 2 divisors, whose sum is σ = 251255618. Its totient is φ = 251255616.

The previous prime is 251255593. The next prime is 251255659. The reversal of 251255617 is 716552152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 193738561 + 57517056 = 13919^2 + 7584^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251255617 is a prime.

It is not a weakly prime, because it can be changed into another prime (251250617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125627808 + 125627809.

It is an arithmetic number, because the mean of its divisors is an integer number (125627809).

Almost surely, 2^251255617 is an apocalyptic number.

It is an amenable number.

251255617 is a deficient number, since it is larger than the sum of its proper divisors (1).

251255617 is an equidigital number, since it uses as much as digits as its factorization.

251255617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21000, while the sum is 34.

The square root of 251255617 is about 15851.0446658887. The cubic root of 251255617 is about 631.0134163979.

The spelling of 251255617 in words is "two hundred fifty-one million, two hundred fifty-five thousand, six hundred seventeen".