257447 has 2 divisors, whose sum is σ = 257448. Its totient is φ = 257446.

The previous prime is 257443. The next prime is 257459. The reversal of 257447 is 744752.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 257447 - 2² = 257443 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128723 + 128724.

It is an arithmetic number, because the mean of its divisors is an integer number (128724).

2²⁵⁷⁴⁴⁷ is an apocalyptic number.

257447 is a deficient number, since it is larger than the sum of its proper divisors (1).

257447 is an equidigital number, since it uses as much as digits as its factorization.

257447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7840, while the sum is 29.

The square root of 257447 is about 507.3923531154. The cubic root of 257447 is about 63.6154511989.

The spelling of 257447 in words is "two hundred fifty-seven thousand, four hundred forty-seven".