9991199 has 2 divisors, whose sum is σ = 9991200. Its totient is φ = 9991198.

The previous prime is 9991187. The next prime is 9991211. The reversal of 9991199 is 9911999.

9991199 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (9991187) and next prime (9991211).

It is a cyclic number.

It is not a de Polignac number, because 9991199 - 2⁴ = 9991183 is a prime.

It is a Sophie Germain prime.

It is a zygodrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9991139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995599 + 4995600.

It is an arithmetic number, because the mean of its divisors is an integer number (4995600).

Almost surely, 2^9991199 is an apocalyptic number.

9991199 is a deficient number, since it is larger than the sum of its proper divisors (1).

9991199 is an equidigital number, since it uses as much as digits as its factorization.

9991199 is an evil number, because the sum of its binary digits is even.

The product of its digits is 59049, while the sum is 47.

The square root of 9991199 is about 3160.8857935712. The cubic root of 9991199 is about 215.3802465198.

The spelling of 9991199 in words is "nine million, nine hundred ninety-one thousand, one hundred ninety-nine".