1257458857 has 2 divisors, whose sum is σ = 1257458858. Its totient is φ = 1257458856.

The previous prime is 1257458849. The next prime is 1257458861. The reversal of 1257458857 is 7588547521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 658384281 + 599074576 = 25659^2 + 24476^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257458857 - 2³ = 1257458849 is a prime.

It is not a weakly prime, because it can be changed into another prime (1257458887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628729428 + 628729429.

It is an arithmetic number, because the mean of its divisors is an integer number (628729429).

Almost surely, 2^1257458857 is an apocalyptic number.

It is an amenable number.

1257458857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257458857 is an equidigital number, since it uses as much as digits as its factorization.

1257458857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3136000, while the sum is 52.

The square root of 1257458857 is about 35460.6663360970. Note that the first 3 decimals coincide. The cubic root of 1257458857 is about 1079.3557133992.

The spelling of 1257458857 in words is "one billion, two hundred fifty-seven million, four hundred fifty-eight thousand, eight hundred fifty-seven".