1161273265 has 16 divisors (see below), whose sum is σ = 1435059648. Its totient is φ = 901607616.

The previous prime is 1161273263. The next prime is 1161273277. The reversal of 1161273265 is 5623721611.

It is a cyclic number.

It is not a de Polignac number, because 1161273265 - 2¹ = 1161273263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1161273265.

It is not an unprimeable number, because it can be changed into a prime (1161273263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16554 + ... + 50956.

It is an arithmetic number, because the mean of its divisors is an integer number (89691228).

Almost surely, 2^1161273265 is an apocalyptic number.

It is an amenable number.

1161273265 is a deficient number, since it is larger than the sum of its proper divisors (273786383).

1161273265 is a wasteful number, since it uses less digits than its factorization.

1161273265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34608.

The product of its digits is 15120, while the sum is 34.

The square root of 1161273265 is about 34077.4597791561. The cubic root of 1161273265 is about 1051.1018712572.

Adding to 1161273265 its reverse (5623721611), we get a palindrome (6784994876).

The spelling of 1161273265 in words is "one billion, one hundred sixty-one million, two hundred seventy-three thousand, two hundred sixty-five".