131009657 has 4 divisors (see below), whose sum is σ = 131033076. Its totient is φ = 130986240.

The previous prime is 131009651. The next prime is 131009687. The reversal of 131009657 is 756900131.

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 130051216 + 958441 = 11404^2 + 979^2 .

It is a cyclic number.

It is not a de Polignac number, because 131009657 - 2¹² = 131005561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131009651) 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, 2153 + ... + 16329.

It is an arithmetic number, because the mean of its divisors is an integer number (32758269).

Almost surely, 2^131009657 is an apocalyptic number.

It is an amenable number.

131009657 is a deficient number, since it is larger than the sum of its proper divisors (23419).

131009657 is an equidigital number, since it uses as much as digits as its factorization.

131009657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23418.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 131009657 is about 11445.9450024889. The cubic root of 131009657 is about 507.8877872823.

Adding to 131009657 its reverse (756900131), we get a palindrome (887909788).

The spelling of 131009657 in words is "one hundred thirty-one million, nine thousand, six hundred fifty-seven".