31313321999 has 4 divisors (see below), whose sum is σ = 31486323960. Its totient is φ = 31140320040.

The previous prime is 31313321957. The next prime is 31313322017. The reversal of 31313321999 is 99912331313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99912331313 = 719 ⋅138960127.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31313321999 is a prime.

It is a super-2 number, since 2×31313321999² (a number of 22 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 (31313321899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86500709 + ... + 86501070.

It is an arithmetic number, because the mean of its divisors is an integer number (7871580990).

Almost surely, 2^31313321999 is an apocalyptic number.

31313321999 is a deficient number, since it is larger than the sum of its proper divisors (173001961).

31313321999 is a wasteful number, since it uses less digits than its factorization.

31313321999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173001960.

The product of its digits is 118098, while the sum is 44.

The spelling of 31313321999 in words is "thirty-one billion, three hundred thirteen million, three hundred twenty-one thousand, nine hundred ninety-nine".