12820945 has 8 divisors (see below), whose sum is σ = 15442344. Its totient is φ = 10218624.

The previous prime is 12820937. The next prime is 12820961. The reversal of 12820945 is 54902821.

It can be written as a sum of positive squares in 4 ways, for example, as 197136 + 12623809 = 444^2 + 3553^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12820945 - 2³ = 12820937 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3244 + ... + 6013.

It is an arithmetic number, because the mean of its divisors is an integer number (1930293).

Almost surely, 2^12820945 is an apocalyptic number.

It is an amenable number.

12820945 is a deficient number, since it is larger than the sum of its proper divisors (2621399).

12820945 is an equidigital number, since it uses as much as digits as its factorization.

12820945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9539.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 12820945 is about 3580.6347202696. The cubic root of 12820945 is about 234.0489402591.

The spelling of 12820945 in words is "twelve million, eight hundred twenty thousand, nine hundred forty-five".