99990988 has 12 divisors (see below), whose sum is σ = 176533560. Its totient is φ = 49552832.

The previous prime is 99990973. The next prime is 99991009. The reversal of 99990988 is 88909999.

It is a super-3 number, since 3×99990988³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110158 + ... + 111061.

It is an arithmetic number, because the mean of its divisors is an integer number (14711130).

Almost surely, 2^99990988 is an apocalyptic number.

It is an amenable number.

99990988 is a deficient number, since it is larger than the sum of its proper divisors (76542572).

99990988 is a wasteful number, since it uses less digits than its factorization.

99990988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221336 (or 221334 counting only the distinct ones).

The product of its (nonzero) digits is 3779136, while the sum is 61.

The square root of 99990988 is about 9999.5493898475. The cubic root of 99990988 is about 464.1449396095.

The spelling of 99990988 in words is "ninety-nine million, nine hundred ninety thousand, nine hundred eighty-eight".