12731866388 has 18 divisors (see below), whose sum is σ = 22810986954. Its totient is φ = 6217884624.

The previous prime is 12731866387. The next prime is 12731866421. The reversal of 12731866388 is 88366813721.

It can be written as a sum of positive squares in only one way, i.e., 9578145424 + 3153720964 = 97868^2 + 56158^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12731866387) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 853331 + ... + 868122.

It is an arithmetic number, because the mean of its divisors is an integer number (1267277053).

Almost surely, 2^12731866388 is an apocalyptic number.

It is an amenable number.

12731866388 is a deficient number, since it is larger than the sum of its proper divisors (10079120566).

12731866388 is a wasteful number, since it uses less digits than its factorization.

12731866388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1721543 (or 1721498 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 53.

The spelling of 12731866388 in words is "twelve billion, seven hundred thirty-one million, eight hundred sixty-six thousand, three hundred eighty-eight".