12921669 has 6 divisors (see below), whose sum is σ = 18664646. Its totient is φ = 8614440.

The previous prime is 12921613. The next prime is 12921673. The reversal of 12921669 is 96612921.

12921669 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 8191044 + 4730625 = 2862^2 + 2175^2 .

It is not a de Polignac number, because 12921669 - 2¹² = 12917573 is a prime.

It is a super-2 number, since 2×12921669² = 333939059491122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12921679) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 717862 + ... + 717879.

Almost surely, 2^12921669 is an apocalyptic number.

It is an amenable number.

12921669 is a deficient number, since it is larger than the sum of its proper divisors (5742977).

12921669 is a wasteful number, since it uses less digits than its factorization.

12921669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1435747 (or 1435744 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 12921669 is about 3594.6723077354. The cubic root of 12921669 is about 234.6602544933.

The spelling of 12921669 in words is "twelve million, nine hundred twenty-one thousand, six hundred sixty-nine".