1155661165 has 16 divisors (see below), whose sum is σ = 1458143280. Its totient is φ = 878008320.

The previous prime is 1155661159. The next prime is 1155661211. The reversal of 1155661165 is 5611665511.

It can be written as a sum of positive squares in 8 ways, for example, as 88397604 + 1067263561 = 9402^2 + 32669^2 .

It is not a de Polignac number, because 1155661165 - 2¹³ = 1155652973 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56484 + ... + 74173.

It is an arithmetic number, because the mean of its divisors is an integer number (91133955).

Almost surely, 2^1155661165 is an apocalyptic number.

It is an amenable number.

1155661165 is a deficient number, since it is larger than the sum of its proper divisors (302482115).

1155661165 is a wasteful number, since it uses less digits than its factorization.

1155661165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130752.

The product of its digits is 27000, while the sum is 37.

The square root of 1155661165 is about 33995.0167671675. The cubic root of 1155661165 is about 1049.4059118508.

The spelling of 1155661165 in words is "one billion, one hundred fifty-five million, six hundred sixty-one thousand, one hundred sixty-five".