131231899 has 4 divisors (see below), whose sum is σ = 132112800. Its totient is φ = 130351000.

The previous prime is 131231851. The next prime is 131231909. The reversal of 131231899 is 998132131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 998132131 = 1439 ⋅693629.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131231899 is a prime.

It is a super-2 number, since 2×131231899² = 34443622630292402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131231819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440227 + ... + 440524.

It is an arithmetic number, because the mean of its divisors is an integer number (33028200).

Almost surely, 2^131231899 is an apocalyptic number.

131231899 is a deficient number, since it is larger than the sum of its proper divisors (880901).

131231899 is an equidigital number, since it uses as much as digits as its factorization.

131231899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880900.

The product of its digits is 11664, while the sum is 37.

The square root of 131231899 is about 11455.6492177441. The cubic root of 131231899 is about 508.1748150598.

The spelling of 131231899 in words is "one hundred thirty-one million, two hundred thirty-one thousand, eight hundred ninety-nine".