12766821 has 8 divisors (see below), whose sum is σ = 17038944. Its totient is φ = 8502960.

The previous prime is 12766801. The next prime is 12766883. The reversal of 12766821 is 12866721.

12766821 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 a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12766821 - 2¹⁸ = 12504677 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12766801) 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, 4926 + ... + 7056.

It is an arithmetic number, because the mean of its divisors is an integer number (2129868).

Almost surely, 2^12766821 is an apocalyptic number.

It is an amenable number.

12766821 is a deficient number, since it is larger than the sum of its proper divisors (4272123).

12766821 is a wasteful number, since it uses less digits than its factorization.

12766821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4131.

The product of its digits is 8064, while the sum is 33.

The square root of 12766821 is about 3573.0688490428. The cubic root of 12766821 is about 233.7191275345.

The spelling of 12766821 in words is "twelve million, seven hundred sixty-six thousand, eight hundred twenty-one".