531159661 has 4 divisors (see below), whose sum is σ = 532525500. Its totient is φ = 529793824.

The previous prime is 531159647. The next prime is 531159691. The reversal of 531159661 is 166951135.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 380484036 + 150675625 = 19506^2 + 12275^2 .

It is a cyclic number.

It is not a de Polignac number, because 531159661 - 2⁷ = 531159533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 531159661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (531159641) 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, 682336 + ... + 683113.

It is an arithmetic number, because the mean of its divisors is an integer number (133131375).

Almost surely, 2^531159661 is an apocalyptic number.

It is an amenable number.

531159661 is a deficient number, since it is larger than the sum of its proper divisors (1365839).

531159661 is a wasteful number, since it uses less digits than its factorization.

531159661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1365838.

The product of its digits is 24300, while the sum is 37.

The square root of 531159661 is about 23046.9013318494. The cubic root of 531159661 is about 809.8570397498.

The spelling of 531159661 in words is "five hundred thirty-one million, one hundred fifty-nine thousand, six hundred sixty-one".