12821009 has 8 divisors (see below), whose sum is σ = 13891680. Its totient is φ = 11785536.

The previous prime is 12820979. The next prime is 12821021. The reversal of 12821009 is 90012821.

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 12821009 - 2¹⁶ = 12755473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12821059) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8039 + ... + 9500.

It is an arithmetic number, because the mean of its divisors is an integer number (1736460).

Almost surely, 2^12821009 is an apocalyptic number.

It is an amenable number.

12821009 is a deficient number, since it is larger than the sum of its proper divisors (1070671).

12821009 is a wasteful number, since it uses less digits than its factorization.

12821009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17599.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 12821009 is about 3580.6436572214. The cubic root of 12821009 is about 234.0493297028.

The spelling of 12821009 in words is "twelve million, eight hundred twenty-one thousand, nine".