163130581 has 4 divisors (see below), whose sum is σ = 163200492. Its totient is φ = 163060672.

The previous prime is 163130557. The next prime is 163130603. The reversal of 163130581 is 185031361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 185031361 = 61 ⋅3033301.

It can be written as a sum of positive squares in 2 ways, for example, as 154778481 + 8352100 = 12441^2 + 2890^2 .

It is a cyclic number.

It is not a de Polignac number, because 163130581 - 2⁵ = 163130549 is a prime.

It is a super-2 number, since 2×163130581² = 53223172914795122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163130551) 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, 31330 + ... + 36163.

It is an arithmetic number, because the mean of its divisors is an integer number (40800123).

Almost surely, 2^163130581 is an apocalyptic number.

It is an amenable number.

163130581 is a deficient number, since it is larger than the sum of its proper divisors (69911).

163130581 is an equidigital number, since it uses as much as digits as its factorization.

163130581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69910.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 163130581 is about 12772.2582576457. The cubic root of 163130581 is about 546.4013885340.

The spelling of 163130581 in words is "one hundred sixty-three million, one hundred thirty thousand, five hundred eighty-one".