6999409 has 2 divisors, whose sum is σ = 6999410. Its totient is φ = 6999408.

The previous prime is 6999389. The next prime is 6999413. The reversal of 6999409 is 9049996.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6906384 + 93025 = 2628^2 + 305^2 .

It is a cyclic number.

It is not a de Polignac number, because 6999409 - 2⁷ = 6999281 is a prime.

It is not a weakly prime, because it can be changed into another prime (6999449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3499704 + 3499705.

It is an arithmetic number, because the mean of its divisors is an integer number (3499705).

Almost surely, 2^6999409 is an apocalyptic number.

It is an amenable number.

6999409 is a deficient number, since it is larger than the sum of its proper divisors (1).

6999409 is an equidigital number, since it uses as much as digits as its factorization.

6999409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 46.

The square root of 6999409 is about 2645.6396202053. The cubic root of 6999409 is about 191.2877345908.

The spelling of 6999409 in words is "six million, nine hundred ninety-nine thousand, four hundred nine".