131666461 has 4 divisors (see below), whose sum is σ = 135225052. Its totient is φ = 128107872.

The previous prime is 131666449. The next prime is 131666477. The reversal of 131666461 is 164666131.

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 91584900 + 40081561 = 9570^2 + 6331^2 .

It is a cyclic number.

It is not a de Polignac number, because 131666461 - 2⁵ = 131666429 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 (131666401) 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, 1779240 + ... + 1779313.

It is an arithmetic number, because the mean of its divisors is an integer number (33806263).

Almost surely, 2^131666461 is an apocalyptic number.

It is an amenable number.

131666461 is a deficient number, since it is larger than the sum of its proper divisors (3558591).

131666461 is an equidigital number, since it uses as much as digits as its factorization.

131666461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3558590.

The product of its digits is 15552, while the sum is 34.

The square root of 131666461 is about 11474.6006902201. The cubic root of 131666461 is about 508.7351212982.

The spelling of 131666461 in words is "one hundred thirty-one million, six hundred sixty-six thousand, four hundred sixty-one".