131723999 has 4 divisors (see below), whose sum is σ = 143698920. Its totient is φ = 119749080.

The previous prime is 131723981. The next prime is 131724001. The reversal of 131723999 is 999327131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999327131 = 11 ⋅90847921.

It is not a de Polignac number, because 131723999 - 2²⁰ = 130675423 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 (131723699) 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, 5987444 + ... + 5987465.

It is an arithmetic number, because the mean of its divisors is an integer number (35924730).

Almost surely, 2^131723999 is an apocalyptic number.

131723999 is a deficient number, since it is larger than the sum of its proper divisors (11974921).

131723999 is a wasteful number, since it uses less digits than its factorization.

131723999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11974920.

The product of its digits is 91854, while the sum is 44.

The square root of 131723999 is about 11477.1076060129. The cubic root of 131723999 is about 508.8092159419.

It can be divided in two parts, 13172 and 3999, that added together give a palindrome (17171).

The spelling of 131723999 in words is "one hundred thirty-one million, seven hundred twenty-three thousand, nine hundred ninety-nine".