12731638320 has 200 divisors, whose sum is σ = 44969688720. Its totient is φ = 3337459200.

The previous prime is 12731638303. The next prime is 12731638327. The reversal of 12731638320 is 2383613721.

12731638320 is a `hidden beast` number, since 1 + 273 + 1 + 6 + 383 + 2 + 0 = 666.

It is a super-2 number, since 2×12731638320² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (12731638327) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 365670 + ... + 398970.

Almost surely, 2^12731638320 is an apocalyptic number.

12731638320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12731638320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22484844360).

12731638320 is an abundant number, since it is smaller than the sum of its proper divisors (32238050400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12731638320 is a wasteful number, since it uses less digits than its factorization.

12731638320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33385 (or 33370 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The spelling of 12731638320 in words is "twelve billion, seven hundred thirty-one million, six hundred thirty-eight thousand, three hundred twenty".