131531639 has 2 divisors, whose sum is σ = 131531640. Its totient is φ = 131531638.

The previous prime is 131531629. The next prime is 131531657. The reversal of 131531639 is 936135131.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 131531639 - 2²⁰ = 130483063 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131531629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65765819 + 65765820.

It is an arithmetic number, because the mean of its divisors is an integer number (65765820).

Almost surely, 2^131531639 is an apocalyptic number.

131531639 is a deficient number, since it is larger than the sum of its proper divisors (1).

131531639 is an equidigital number, since it uses as much as digits as its factorization.

131531639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7290, while the sum is 32.

The square root of 131531639 is about 11468.7243841676. The cubic root of 131531639 is about 508.5614194808.

The spelling of 131531639 in words is "one hundred thirty-one million, five hundred thirty-one thousand, six hundred thirty-nine".