1265173057 has 4 divisors (see below), whose sum is σ = 1265422896. Its totient is φ = 1264923220.

The previous prime is 1265173051. The next prime is 1265173061. The reversal of 1265173057 is 7503715621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1265173057 - 2¹⁹ = 1264648769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265173051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117163 + ... + 127504.

It is an arithmetic number, because the mean of its divisors is an integer number (316355724).

Almost surely, 2^1265173057 is an apocalyptic number.

It is an amenable number.

1265173057 is a deficient number, since it is larger than the sum of its proper divisors (249839).

1265173057 is an equidigital number, since it uses as much as digits as its factorization.

1265173057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249838.

The product of its (nonzero) digits is 44100, while the sum is 37.

The square root of 1265173057 is about 35569.2712464003. The cubic root of 1265173057 is about 1081.5584089012.

Adding to 1265173057 its reverse (7503715621), we get a palindrome (8768888678).

The spelling of 1265173057 in words is "one billion, two hundred sixty-five million, one hundred seventy-three thousand, fifty-seven".