12721320 has 64 divisors (see below), whose sum is σ = 42408000. Its totient is φ = 3392064.

The previous prime is 12721273. The next prime is 12721333. The reversal of 12721320 is 2312721.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 12721293 and 12721302.

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, 4810 + ... + 6969.

It is an arithmetic number, because the mean of its divisors is an integer number (662625).

Almost surely, 2^12721320 is an apocalyptic number.

12721320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12721320 is an abundant number, since it is smaller than the sum of its proper divisors (29686680).

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

12721320 is a wasteful number, since it uses less digits than its factorization.

12721320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11799 (or 11789 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 12721320 is about 3566.6959500356. The cubic root of 12721320 is about 233.4411383927.

It can be divided in two parts, 12721 and 320, that added together give a triangular number (13041 = T₁₆₁).

The spelling of 12721320 in words is "twelve million, seven hundred twenty-one thousand, three hundred twenty".