1257745057 has 4 divisors (see below), whose sum is σ = 1257823636. Its totient is φ = 1257666480.

The previous prime is 1257745043. The next prime is 1257745061. The reversal of 1257745057 is 7505477521.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 271722256 + 986022801 = 16484^2 + 31401^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257745057 - 2¹¹ = 1257743009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1257745157) 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 in 3 ways as a sum of consecutive naturals, for example, 5718 + ... + 50479.

It is an arithmetic number, because the mean of its divisors is an integer number (314455909).

Almost surely, 2^1257745057 is an apocalyptic number.

It is an amenable number.

1257745057 is a deficient number, since it is larger than the sum of its proper divisors (78579).

1257745057 is an equidigital number, since it uses as much as digits as its factorization.

1257745057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78578.

The product of its (nonzero) digits is 343000, while the sum is 43.

The square root of 1257745057 is about 35464.7015636675. The cubic root of 1257745057 is about 1079.4375949839.

The spelling of 1257745057 in words is "one billion, two hundred fifty-seven million, seven hundred forty-five thousand, fifty-seven".