159569681 has 4 divisors (see below), whose sum is σ = 159597492. Its totient is φ = 159541872.

The previous prime is 159569677. The next prime is 159569693. The reversal of 159569681 is 186965951.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186965951 = 131 ⋅1427221.

It can be written as a sum of positive squares in 2 ways, for example, as 35046400 + 124523281 = 5920^2 + 11159^2 .

It is a cyclic number.

It is not a de Polignac number, because 159569681 - 2² = 159569677 is a prime.

It is a super-2 number, since 2×159569681² = 50924966188883522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (159569611) 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, 1766 + ... + 17951.

It is an arithmetic number, because the mean of its divisors is an integer number (39899373).

Almost surely, 2^159569681 is an apocalyptic number.

It is an amenable number.

159569681 is a deficient number, since it is larger than the sum of its proper divisors (27811).

159569681 is an equidigital number, since it uses as much as digits as its factorization.

159569681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27810.

The product of its digits is 583200, while the sum is 50.

The square root of 159569681 is about 12632.0893362895. The cubic root of 159569681 is about 542.3963923981.

The spelling of 159569681 in words is "one hundred fifty-nine million, five hundred sixty-nine thousand, six hundred eighty-one".