6823721 has 2 divisors, whose sum is σ = 6823722. Its totient is φ = 6823720.

The previous prime is 6823703. The next prime is 6823757. The reversal of 6823721 is 1273286.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6817321 + 6400 = 2611^2 + 80^2 .

It is a cyclic number.

It is not a de Polignac number, because 6823721 - 2⁶ = 6823657 is a prime.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (6823771) 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 as a sum of consecutive naturals, namely, 3411860 + 3411861.

It is an arithmetic number, because the mean of its divisors is an integer number (3411861).

Almost surely, 2^6823721 is an apocalyptic number.

It is an amenable number.

6823721 is a deficient number, since it is larger than the sum of its proper divisors (1).

6823721 is an equidigital number, since it uses as much as digits as its factorization.

6823721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 29.

The square root of 6823721 is about 2612.2252965623. The cubic root of 6823721 is about 189.6736873609.

The spelling of 6823721 in words is "six million, eight hundred twenty-three thousand, seven hundred twenty-one".