1165333261 has 4 divisors (see below), whose sum is σ = 1165772224. Its totient is φ = 1164894300.

The previous prime is 1165333259. The next prime is 1165333271. The reversal of 1165333261 is 1623335611.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1623335611 = 1217 ⋅1333883.

It is a cyclic number.

It is not a de Polignac number, because 1165333261 - 2¹ = 1165333259 is a prime.

It is a super-3 number, since 3×1165333261³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1165333231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215475 + ... + 220816.

It is an arithmetic number, because the mean of its divisors is an integer number (291443056).

Almost surely, 2^1165333261 is an apocalyptic number.

It is an amenable number.

1165333261 is a deficient number, since it is larger than the sum of its proper divisors (438963).

1165333261 is an equidigital number, since it uses as much as digits as its factorization.

1165333261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438962.

The product of its digits is 9720, while the sum is 31.

The square root of 1165333261 is about 34136.9779125218. The cubic root of 1165333261 is about 1052.3253862581.

Adding to 1165333261 its reverse (1623335611), we get a palindrome (2788668872).

The spelling of 1165333261 in words is "one billion, one hundred sixty-five million, three hundred thirty-three thousand, two hundred sixty-one".