131206639 has 2 divisors, whose sum is σ = 131206640. Its totient is φ = 131206638.

The previous prime is 131206613. The next prime is 131206661. The reversal of 131206639 is 936602131.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 131206639 - 2⁷ = 131206511 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131206639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131206139) 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, 65603319 + 65603320.

It is an arithmetic number, because the mean of its divisors is an integer number (65603320).

Almost surely, 2^131206639 is an apocalyptic number.

131206639 is a deficient number, since it is larger than the sum of its proper divisors (1).

131206639 is an equidigital number, since it uses as much as digits as its factorization.

131206639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 131206639 is about 11454.5466518758. The cubic root of 131206639 is about 508.1422078466.

The spelling of 131206639 in words is "one hundred thirty-one million, two hundred six thousand, six hundred thirty-nine".