251257 has 2 divisors, whose sum is σ = 251258. Its totient is φ = 251256.

The previous prime is 251233. The next prime is 251261. The reversal of 251257 is 752152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 251001 + 256 = 501^2 + 16^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251257 is a prime.

It is a plaindrome in base 14.

It is not a weakly prime, because it can be changed into another prime (251287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125628 + 125629.

It is an arithmetic number, because the mean of its divisors is an integer number (125629).

2²⁵¹²⁵⁷ is an apocalyptic number.

It is an amenable number.

251257 is a deficient number, since it is larger than the sum of its proper divisors (1).

251257 is an equidigital number, since it uses as much as digits as its factorization.

251257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 700, while the sum is 22.

The square root of 251257 is about 501.2554239108. The cubic root of 251257 is about 63.1014574170.

The spelling of 251257 in words is "two hundred fifty-one thousand, two hundred fifty-seven".