9900091 has 2 divisors, whose sum is σ = 9900092. Its totient is φ = 9900090.

The previous prime is 9900047. The next prime is 9900101. The reversal of 9900091 is 1900099.

9900091 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9900091 - 2⁷ = 9899963 is a prime.

It is not a weakly prime, because it can be changed into another prime (9900391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4950045 + 4950046.

It is an arithmetic number, because the mean of its divisors is an integer number (4950046).

Almost surely, 2^9900091 is an apocalyptic number.

9900091 is a deficient number, since it is larger than the sum of its proper divisors (1).

9900091 is an equidigital number, since it uses as much as digits as its factorization.

9900091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 729, while the sum is 28.

The square root of 9900091 is about 3146.4410053265. The cubic root of 9900091 is about 214.7235748051.

The spelling of 9900091 in words is "nine million, nine hundred thousand, ninety-one".