9999399 has 4 divisors (see below), whose sum is σ = 13332536. Its totient is φ = 6666264.

The previous prime is 9999397. The next prime is 9999401. The reversal of 9999399 is 9939999.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (9999397) and next prime (9999401).

It is not a de Polignac number, because 9999399 - 2¹ = 9999397 is a prime.

It is a super-2 number, since 2×9999399² = 199975960722402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1666564 + ... + 1666569.

It is an arithmetic number, because the mean of its divisors is an integer number (3333134).

Almost surely, 2^9999399 is an apocalyptic number.

9999399 is a deficient number, since it is larger than the sum of its proper divisors (3333137).

9999399 is a wasteful number, since it uses less digits than its factorization.

9999399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3333136.

The product of its digits is 1594323, while the sum is 57.

The square root of 9999399 is about 3162.1826322969. The cubic root of 9999399 is about 215.4391528659.

The spelling of 9999399 in words is "nine million, nine hundred ninety-nine thousand, three hundred ninety-nine".