20131331999 has 4 divisors (see below), whose sum is σ = 20131621320. Its totient is φ = 20131042680.

The previous prime is 20131331993. The next prime is 20131332041. The reversal of 20131331999 is 99913313102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20131331999 - 2⁸ = 20131331743 is a prime.

It is a super-2 number, since 2×20131331999² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20131331993) 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, 30032 + ... + 202890.

It is an arithmetic number, because the mean of its divisors is an integer number (5032905330).

Almost surely, 2^20131331999 is an apocalyptic number.

20131331999 is a deficient number, since it is larger than the sum of its proper divisors (289321).

20131331999 is a wasteful number, since it uses less digits than its factorization.

20131331999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289320.

The product of its (nonzero) digits is 39366, while the sum is 41.

The spelling of 20131331999 in words is "twenty billion, one hundred thirty-one million, three hundred thirty-one thousand, nine hundred ninety-nine".