6904721 has 2 divisors, whose sum is σ = 6904722. Its totient is φ = 6904720.

The previous prime is 6904693. The next prime is 6904727. The reversal of 6904721 is 1274096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6574096 + 330625 = 2564^2 + 575^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6904721 is a prime.

It is a Sophie Germain prime.

It is a d-powerful number, because it can be written as 6⁵ + 9⁷ + 0 + 4² + 7⁵ + 2²¹ + 1 .

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (6904727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3452360 + 3452361.

It is an arithmetic number, because the mean of its divisors is an integer number (3452361).

Almost surely, 2^6904721 is an apocalyptic number.

It is an amenable number.

6904721 is a deficient number, since it is larger than the sum of its proper divisors (1).

6904721 is an equidigital number, since it uses as much as digits as its factorization.

6904721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 6904721 is about 2627.6835806467. The cubic root of 6904721 is about 190.4212353178.

The spelling of 6904721 in words is "six million, nine hundred four thousand, seven hundred twenty-one".