9099090991 has 4 divisors (see below), whose sum is σ = 9182569000. Its totient is φ = 9015612984.

The previous prime is 9099090947. The next prime is 9099090997. The reversal of 9099090991 is 1990909909.

It is a happy number.

9099090991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 9099090991 - 2⁹ = 9099090479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9099090997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41738841 + ... + 41739058.

It is an arithmetic number, because the mean of its divisors is an integer number (2295642250).

Almost surely, 2^9099090991 is an apocalyptic number.

9099090991 is a deficient number, since it is larger than the sum of its proper divisors (83478009).

9099090991 is a wasteful number, since it uses less digits than its factorization.

9099090991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83478008.

The product of its (nonzero) digits is 531441, while the sum is 55.

The square root of 9099090991 is about 95389.1555209501. The cubic root of 9099090991 is about 2087.6899601524.

The spelling of 9099090991 in words is "nine billion, ninety-nine million, ninety thousand, nine hundred ninety-one".