1257275745 has 24 divisors (see below), whose sum is σ = 2377395072. Its totient is φ = 609588000.

The previous prime is 1257275741. The next prime is 1257275779. The reversal of 1257275745 is 5475727521.

1257275745 is a `hidden beast` number, since 1 + 2 + 5 + 72 + 7 + 574 + 5 = 666.

It is not a de Polignac number, because 1257275745 - 2² = 1257275741 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1257275745.

It is not an unprimeable number, because it can be changed into a prime (1257275741) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1269481 + ... + 1270470.

It is an arithmetic number, because the mean of its divisors is an integer number (99058128).

Almost surely, 2^1257275745 is an apocalyptic number.

1257275745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1257275745 is a deficient number, since it is larger than the sum of its proper divisors (1120119327).

1257275745 is a wasteful number, since it uses less digits than its factorization.

1257275745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2539973 (or 2539970 counting only the distinct ones).

The product of its digits is 686000, while the sum is 45.

The square root of 1257275745 is about 35458.0843391179. The cubic root of 1257275745 is about 1079.3033186889.

The spelling of 1257275745 in words is "one billion, two hundred fifty-seven million, two hundred seventy-five thousand, seven hundred forty-five".