6812221 has 12 divisors (see below), whose sum is σ = 7451028. Its totient is φ = 6225024.

The previous prime is 6812207. The next prime is 6812231. The reversal of 6812221 is 1222186.

It can be written as a sum of positive squares in 6 ways, for example, as 632025 + 6180196 = 795^2 + 2486^2 .

It is not a de Polignac number, because 6812221 - 2¹⁵ = 6779453 is a prime.

6812221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 6812192 and 6812201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6812231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29121 + ... + 29353.

It is an arithmetic number, because the mean of its divisors is an integer number (620919).

Almost surely, 2^6812221 is an apocalyptic number.

It is an amenable number.

6812221 is a deficient number, since it is larger than the sum of its proper divisors (638807).

6812221 is a wasteful number, since it uses less digits than its factorization.

6812221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 419 counting only the distinct ones).

The product of its digits is 384, while the sum is 22.

The square root of 6812221 is about 2610.0231799737. The cubic root of 6812221 is about 189.5670752498.

The spelling of 6812221 in words is "six million, eight hundred twelve thousand, two hundred twenty-one".