12906021 has 16 divisors (see below), whose sum is σ = 17736768. Its totient is φ = 8342400.

The previous prime is 12906017. The next prime is 12906029. The reversal of 12906021 is 12060921.

12906021 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12906021 - 2² = 12906017 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12906029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38826 + ... + 39156.

It is an arithmetic number, because the mean of its divisors is an integer number (1108548).

Almost surely, 2^12906021 is an apocalyptic number.

It is an amenable number.

12906021 is a deficient number, since it is larger than the sum of its proper divisors (4830747).

12906021 is a wasteful number, since it uses less digits than its factorization.

12906021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 692.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 12906021 is about 3592.4950939424. The cubic root of 12906021 is about 234.5654925629.

Adding to 12906021 its reverse (12060921), we get a palindrome (24966942).

The spelling of 12906021 in words is "twelve million, nine hundred six thousand, twenty-one".