1161320511 has 12 divisors (see below), whose sum is σ = 1676700168. Its totient is φ = 714658464.

The previous prime is 1161320497. The next prime is 1161320557. The reversal of 1161320511 is 1150231611.

It is a happy number.

It is not a de Polignac number, because 1161320511 - 2⁷ = 1161320383 is a prime.

It is a super-2 number, since 2×1161320511² = 2697330658538602242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1161320911) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1144780 + ... + 1145793.

It is an arithmetic number, because the mean of its divisors is an integer number (139725014).

Almost surely, 2^1161320511 is an apocalyptic number.

1161320511 is a deficient number, since it is larger than the sum of its proper divisors (515379657).

1161320511 is a wasteful number, since it uses less digits than its factorization.

1161320511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2290602 (or 2290589 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 21.

The square root of 1161320511 is about 34078.1529869211. The cubic root of 1161320511 is about 1051.1161256356.

Subtracting from 1161320511 its reverse (1150231611), we obtain a square (11088900 = 3330²).

The spelling of 1161320511 in words is "one billion, one hundred sixty-one million, three hundred twenty thousand, five hundred eleven".