131305631 has 2 divisors, whose sum is σ = 131305632. Its totient is φ = 131305630.

The previous prime is 131305613. The next prime is 131305673. The reversal of 131305631 is 136503131.

It is a happy number.

Together with previous prime (131305613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 131305631 - 2⁶ = 131305567 is a prime.

It is a super-2 number, since 2×131305631² = 34482337464616322, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 131305597 and 131305606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131305231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65652815 + 65652816.

It is an arithmetic number, because the mean of its divisors is an integer number (65652816).

Almost surely, 2^131305631 is an apocalyptic number.

131305631 is a deficient number, since it is larger than the sum of its proper divisors (1).

131305631 is an equidigital number, since it uses as much as digits as its factorization.

131305631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 131305631 is about 11458.8669160611. The cubic root of 131305631 is about 508.2699690854.

Adding to 131305631 its reverse (136503131), we get a palindrome (267808762).

The spelling of 131305631 in words is "one hundred thirty-one million, three hundred five thousand, six hundred thirty-one".