31868518369 has 4 divisors (see below), whose sum is σ = 31992520644. Its totient is φ = 31744516096.

The previous prime is 31868518333. The next prime is 31868518387. The reversal of 31868518369 is 96381586813.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 96381586813 = 265427 ⋅363119.

It can be written as a sum of positive squares in 2 ways, for example, as 20137029025 + 11731489344 = 141905^2 + 108312^2 .

It is a cyclic number.

It is not a de Polignac number, because 31868518369 - 2¹⁵ = 31868485601 is a prime.

It is a super-2 number, since 2×31868518369² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31868518069) 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, 62000752 + ... + 62001265.

It is an arithmetic number, because the mean of its divisors is an integer number (7998130161).

Almost surely, 2^31868518369 is an apocalyptic number.

It is an amenable number.

31868518369 is a deficient number, since it is larger than the sum of its proper divisors (124002275).

31868518369 is a wasteful number, since it uses less digits than its factorization.

31868518369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124002274.

The product of its digits is 7464960, while the sum is 58.

The spelling of 31868518369 in words is "thirty-one billion, eight hundred sixty-eight million, five hundred eighteen thousand, three hundred sixty-nine".