12731520 has 128 divisors (see below), whose sum is σ = 42840000. Its totient is φ = 3207168.

The previous prime is 12731503. The next prime is 12731531. The reversal of 12731520 is 2513721.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36306 + ... + 36654.

Almost surely, 2^12731520 is an apocalyptic number.

12731520 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 12731520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21420000).

12731520 is an abundant number, since it is smaller than the sum of its proper divisors (30108480).

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

12731520 is a wasteful number, since it uses less digits than its factorization.

12731520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 378 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 12731520 is about 3568.1255583289. The cubic root of 12731520 is about 233.5035130389.

The spelling of 12731520 in words is "twelve million, seven hundred thirty-one thousand, five hundred twenty".