99109000991 has 16 divisors (see below), whose sum is σ = 133069429248. Its totient is φ = 71287192800.

The previous prime is 99109000943. The next prime is 99109001039. The reversal of 99109000991 is 19900090199.

It is an interprime number because it is at equal distance from previous prime (99109000943) and next prime (99109001039).

It is a cyclic number.

It is not a de Polignac number, because 99109000991 - 2²⁶ = 99041892127 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99109000391) 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, 49503995 + ... + 49505996.

It is an arithmetic number, because the mean of its divisors is an integer number (8316839328).

Almost surely, 2^99109000991 is an apocalyptic number.

99109000991 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

99109000991 is a deficient number, since it is larger than the sum of its proper divisors (33960428257).

99109000991 is a wasteful number, since it uses less digits than its factorization.

99109000991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99010022.

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

The spelling of 99109000991 in words is "ninety-nine billion, one hundred nine million, nine hundred ninety-one", and thus it is an aban number.