131257561 has 8 divisors (see below), whose sum is σ = 139980960. Its totient is φ = 122645568.

The previous prime is 131257559. The next prime is 131257579. The reversal of 131257561 is 165752131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 131257561 - 2¹ = 131257559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131257501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25411 + ... + 30136.

It is an arithmetic number, because the mean of its divisors is an integer number (17497620).

Almost surely, 2^131257561 is an apocalyptic number.

It is an amenable number.

131257561 is a deficient number, since it is larger than the sum of its proper divisors (8723399).

131257561 is a wasteful number, since it uses less digits than its factorization.

131257561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55703.

The product of its digits is 6300, while the sum is 31.

The square root of 131257561 is about 11456.7692217309. The cubic root of 131257561 is about 508.2079369157.

The spelling of 131257561 in words is "one hundred thirty-one million, two hundred fifty-seven thousand, five hundred sixty-one".