257117657 has 2 divisors, whose sum is σ = 257117658. Its totient is φ = 257117656.

The previous prime is 257117647. The next prime is 257117677. The reversal of 257117657 is 756711752.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 253319056 + 3798601 = 15916^2 + 1949^2 .

It is a cyclic number.

It is not a de Polignac number, because 257117657 - 2¹⁰ = 257116633 is a prime.

It is a super-2 number, since 2×257117657² = 132218979082339298, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (257117647) 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, 128558828 + 128558829.

It is an arithmetic number, because the mean of its divisors is an integer number (128558829).

Almost surely, 2^257117657 is an apocalyptic number.

It is an amenable number.

257117657 is a deficient number, since it is larger than the sum of its proper divisors (1).

257117657 is an equidigital number, since it uses as much as digits as its factorization.

257117657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 102900, while the sum is 41.

The square root of 257117657 is about 16034.8887429879. Note that the first 3 decimals coincide. The cubic root of 257117657 is about 635.8831261119.

The spelling of 257117657 in words is "two hundred fifty-seven million, one hundred seventeen thousand, six hundred fifty-seven".