99008991 has 12 divisors (see below), whose sum is σ = 143805480. Its totient is φ = 65640240.

The previous prime is 99008989. The next prime is 99008999. The reversal of 99008991 is 19980099.

It is not a de Polignac number, because 99008991 - 2¹ = 99008989 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

99008991 is a modest number, since divided by 8991 gives 99 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99008999) 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 11 ways as a sum of consecutive naturals, for example, 28761 + ... + 32018.

It is an arithmetic number, because the mean of its divisors is an integer number (11983790).

Almost surely, 2^99008991 is an apocalyptic number.

99008991 is a deficient number, since it is larger than the sum of its proper divisors (44796489).

99008991 is a wasteful number, since it uses less digits than its factorization.

99008991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60966 (or 60963 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The square root of 99008991 is about 9950.3261755583. The cubic root of 99008991 is about 462.6205048548.

It can be divided in two parts, 99008 and 991, that added together give a palindrome (99999).

The spelling of 99008991 in words is "ninety-nine million, eight thousand, nine hundred ninety-one".