1165571653 has 4 divisors (see below), whose sum is σ = 1165825440. Its totient is φ = 1165317868.

The previous prime is 1165571647. The next prime is 1165571681. The reversal of 1165571653 is 3561755611.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1165571653 - 2²⁵ = 1132017221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1165574653) 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, 119875 + ... + 129232.

It is an arithmetic number, because the mean of its divisors is an integer number (291456360).

Almost surely, 2^1165571653 is an apocalyptic number.

It is an amenable number.

1165571653 is a deficient number, since it is larger than the sum of its proper divisors (253787).

1165571653 is an equidigital number, since it uses as much as digits as its factorization.

1165571653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253786.

The product of its digits is 94500, while the sum is 40.

The square root of 1165571653 is about 34140.4694314533. The cubic root of 1165571653 is about 1052.3971393658.

The spelling of 1165571653 in words is "one billion, one hundred sixty-five million, five hundred seventy-one thousand, six hundred fifty-three".