1165611505 has 4 divisors (see below), whose sum is σ = 1398733812. Its totient is φ = 932489200.

The previous prime is 1165611497. The next prime is 1165611523. The reversal of 1165611505 is 5051165611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5051165611 = 83 ⋅60857417.

It can be written as a sum of positive squares in 2 ways, for example, as 142635249 + 1022976256 = 11943^2 + 31984^2 .

It is not a de Polignac number, because 1165611505 - 2³ = 1165611497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116561146 + ... + 116561155.

It is an arithmetic number, because the mean of its divisors is an integer number (349683453).

Almost surely, 2^1165611505 is an apocalyptic number.

It is an amenable number.

1165611505 is a deficient number, since it is larger than the sum of its proper divisors (233122307).

1165611505 is an equidigital number, since it uses as much as digits as its factorization.

1165611505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233122306.

The product of its (nonzero) digits is 4500, while the sum is 31.

The square root of 1165611505 is about 34141.0530739753. The cubic root of 1165611505 is about 1052.4091333811.

The spelling of 1165611505 in words is "one billion, one hundred sixty-five million, six hundred eleven thousand, five hundred five".