6999399 has 16 divisors (see below), whose sum is σ = 11312640. Its totient is φ = 4241880.

The previous prime is 6999389. The next prime is 6999409. The reversal of 6999399 is 9939996.

It is an interprime number because it is at equal distance from previous prime (6999389) and next prime (6999409).

It is not a de Polignac number, because 6999399 - 2⁵ = 6999367 is a prime.

It is a super-2 number, since 2×6999399² = 97983172722402, which contains 22 as substring.

6999399 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6999379) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11487 + ... + 12080.

It is an arithmetic number, because the mean of its divisors is an integer number (707040).

Almost surely, 2^6999399 is an apocalyptic number.

6999399 is a deficient number, since it is larger than the sum of its proper divisors (4313241).

6999399 is a wasteful number, since it uses less digits than its factorization.

6999399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23587 (or 23581 counting only the distinct ones).

The product of its digits is 1062882, while the sum is 54.

The square root of 6999399 is about 2645.6377303025. The cubic root of 6999399 is about 191.2876434937.

The spelling of 6999399 in words is "six million, nine hundred ninety-nine thousand, three hundred ninety-nine".