131031999 has 40 divisors (see below), whose sum is σ = 235495040. Its totient is φ = 70928784.

The previous prime is 131031997. The next prime is 131032067. The reversal of 131031999 is 999130131.

It is not a de Polignac number, because 131031999 - 2¹ = 131031997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131031997) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4692 + ... + 16854.

It is an arithmetic number, because the mean of its divisors is an integer number (5887376).

Almost surely, 2^131031999 is an apocalyptic number.

131031999 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

131031999 is a deficient number, since it is larger than the sum of its proper divisors (104463041).

131031999 is a wasteful number, since it uses less digits than its factorization.

131031999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12201 (or 12192 counting only the distinct ones).

The product of its (nonzero) digits is 6561, while the sum is 36.

The square root of 131031999 is about 11446.9209397113. The cubic root of 131031999 is about 507.9166568690.

The spelling of 131031999 in words is "one hundred thirty-one million, thirty-one thousand, nine hundred ninety-nine".