131031997 has 2 divisors, whose sum is σ = 131031998. Its totient is φ = 131031996.

The previous prime is 131031983. The next prime is 131032067. The reversal of 131031997 is 799130131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84437721 + 46594276 = 9189^2 + 6826^2 .

It is a cyclic number.

It is not a de Polignac number, because 131031997 - 2¹¹ = 131029949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131031917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65515998 + 65515999.

It is an arithmetic number, because the mean of its divisors is an integer number (65515999).

Almost surely, 2^131031997 is an apocalyptic number.

It is an amenable number.

131031997 is a deficient number, since it is larger than the sum of its proper divisors (1).

131031997 is an equidigital number, since it uses as much as digits as its factorization.

131031997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5103, while the sum is 34.

The square root of 131031997 is about 11446.9208523515. The cubic root of 131031997 is about 507.9166542849.

The spelling of 131031997 in words is "one hundred thirty-one million, thirty-one thousand, nine hundred ninety-seven".