1164165561 has 16 divisors (see below), whose sum is σ = 1857358720. Its totient is φ = 716409360.

The previous prime is 1164165551. The next prime is 1164165601. The reversal of 1164165561 is 1655614611.

1164165561 is a `hidden beast` number, since 1 + 1 + 641 + 6 + 5 + 5 + 6 + 1 = 666.

It is not a de Polignac number, because 1164165561 - 2²¹ = 1162068409 is a prime.

It is a super-3 number, since 3×1164165561³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1164165551) 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, 1658005 + ... + 1658706.

It is an arithmetic number, because the mean of its divisors is an integer number (116084920).

Almost surely, 2^1164165561 is an apocalyptic number.

It is an amenable number.

1164165561 is a deficient number, since it is larger than the sum of its proper divisors (693193159).

1164165561 is a wasteful number, since it uses less digits than its factorization.

1164165561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3316733 (or 3316727 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 1164165561 is about 34119.8704716181. The cubic root of 1164165561 is about 1051.9737812551.

The spelling of 1164165561 in words is "one billion, one hundred sixty-four million, one hundred sixty-five thousand, five hundred sixty-one".