131310661 has 4 divisors (see below), whose sum is σ = 131884300. Its totient is φ = 130737024.

The previous prime is 131310643. The next prime is 131310667. The reversal of 131310661 is 166013131.

It is a happy number.

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 123988225 + 7322436 = 11135^2 + 2706^2 .

It is a cyclic number.

It is not a de Polignac number, because 131310661 - 2¹⁹ = 130786373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131310667) 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, 286476 + ... + 286933.

It is an arithmetic number, because the mean of its divisors is an integer number (32971075).

Almost surely, 2^131310661 is an apocalyptic number.

It is an amenable number.

131310661 is a deficient number, since it is larger than the sum of its proper divisors (573639).

131310661 is an equidigital number, since it uses as much as digits as its factorization.

131310661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573638.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 131310661 is about 11459.0863946477. The cubic root of 131310661 is about 508.2764591988.

Adding to 131310661 its reverse (166013131), we get a palindrome (297323792).

The spelling of 131310661 in words is "one hundred thirty-one million, three hundred ten thousand, six hundred sixty-one".