1257165745 has 16 divisors (see below), whose sum is σ = 1646460288. Its totient is φ = 913904640.

The previous prime is 1257165731. The next prime is 1257165769. The reversal of 1257165745 is 5475617521.

It is not a de Polignac number, because 1257165745 - 2²¹ = 1255068593 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195217 + ... + 201553.

It is an arithmetic number, because the mean of its divisors is an integer number (102903768).

Almost surely, 2^1257165745 is an apocalyptic number.

It is an amenable number.

1257165745 is a deficient number, since it is larger than the sum of its proper divisors (389294543).

1257165745 is a wasteful number, since it uses less digits than its factorization.

1257165745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9960.

The product of its digits is 294000, while the sum is 43.

The square root of 1257165745 is about 35456.5331779631. The cubic root of 1257165745 is about 1079.2718414180.

The spelling of 1257165745 in words is "one billion, two hundred fifty-seven million, one hundred sixty-five thousand, seven hundred forty-five".