257487557 has 2 divisors, whose sum is σ = 257487558. Its totient is φ = 257487556.

The previous prime is 257487541. The next prime is 257487577. The reversal of 257487557 is 755784752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 247558756 + 9928801 = 15734^2 + 3151^2 .

It is a cyclic number.

It is not a de Polignac number, because 257487557 - 2⁴ = 257487541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257487577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128743778 + 128743779.

It is an arithmetic number, because the mean of its divisors is an integer number (128743779).

Almost surely, 2^257487557 is an apocalyptic number.

It is an amenable number.

257487557 is a deficient number, since it is larger than the sum of its proper divisors (1).

257487557 is an equidigital number, since it uses as much as digits as its factorization.

257487557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2744000, while the sum is 50.

The square root of 257487557 is about 16046.4188216561. The cubic root of 257487557 is about 636.1879158404.

The spelling of 257487557 in words is "two hundred fifty-seven million, four hundred eighty-seven thousand, five hundred fifty-seven".