1257695057 has 2 divisors, whose sum is σ = 1257695058. Its totient is φ = 1257695056.

The previous prime is 1257695053. The next prime is 1257695059. The reversal of 1257695057 is 7505967521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1131716881 + 125978176 = 33641^2 + 11224^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257695057 - 2² = 1257695053 is a prime.

Together with 1257695059, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1257695053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628847528 + 628847529.

It is an arithmetic number, because the mean of its divisors is an integer number (628847529).

Almost surely, 2^1257695057 is an apocalyptic number.

It is an amenable number.

1257695057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257695057 is an equidigital number, since it uses as much as digits as its factorization.

1257695057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 661500, while the sum is 47.

The square root of 1257695057 is about 35463.9966303856. The cubic root of 1257695057 is about 1079.4232909206.

The spelling of 1257695057 in words is "one billion, two hundred fifty-seven million, six hundred ninety-five thousand, fifty-seven".