12721345 has 32 divisors (see below), whose sum is σ = 19095552. Its totient is φ = 7921152.

The previous prime is 12721333. The next prime is 12721361. The reversal of 12721345 is 54312721.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 12721345 - 2⁷ = 12721217 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33024 + ... + 33406.

It is an arithmetic number, because the mean of its divisors is an integer number (596736).

Almost surely, 2^12721345 is an apocalyptic number.

It is an amenable number.

12721345 is a deficient number, since it is larger than the sum of its proper divisors (6374207).

12721345 is a wasteful number, since it uses less digits than its factorization.

12721345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481.

The product of its digits is 1680, while the sum is 25.

The square root of 12721345 is about 3566.6994546780. The cubic root of 12721345 is about 233.4412913125.

The spelling of 12721345 in words is "twelve million, seven hundred twenty-one thousand, three hundred forty-five".