99999081 has 24 divisors (see below), whose sum is σ = 177777600. Its totient is φ = 52746336.

The previous prime is 99999079. The next prime is 99999089. The reversal of 99999081 is 18099999.

It is not a de Polignac number, because 99999081 - 2¹ = 99999079 is a prime.

It is a super-2 number, since 2×99999081² = 19999632401689122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (99999089) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60231 + ... + 61868.

It is an arithmetic number, because the mean of its divisors is an integer number (7407400).

Almost surely, 2^99999081 is an apocalyptic number.

99999081 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

It is an amenable number.

99999081 is a deficient number, since it is larger than the sum of its proper divisors (77778519).

99999081 is a wasteful number, since it uses less digits than its factorization.

99999081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122125 (or 122122 counting only the distinct ones).

The product of its (nonzero) digits is 472392, while the sum is 54.

The square root of 99999081 is about 9999.9540498944. The cubic root of 99999081 is about 464.1574614835.

The spelling of 99999081 in words is "ninety-nine million, nine hundred ninety-nine thousand, eighty-one".