99988281 has 6 divisors (see below), whose sum is σ = 144427530. Its totient is φ = 66658848.

The previous prime is 99988277. The next prime is 99988289. The reversal of 99988281 is 18288999.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 99680256 + 308025 = 9984^2 + 555^2 .

It is not a de Polignac number, because 99988281 - 2² = 99988277 is a prime.

It is a super-2 number, since 2×99988281² = 19995312674669922, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (99988289) 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 5 ways as a sum of consecutive naturals, for example, 5554896 + ... + 5554913.

It is an arithmetic number, because the mean of its divisors is an integer number (24071255).

Almost surely, 2^99988281 is an apocalyptic number.

It is an amenable number.

99988281 is a deficient number, since it is larger than the sum of its proper divisors (44439249).

99988281 is a wasteful number, since it uses less digits than its factorization.

99988281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11109815 (or 11109812 counting only the distinct ones).

The product of its digits is 746496, while the sum is 54.

The square root of 99988281 is about 9999.4140328321. The cubic root of 99988281 is about 464.1407510598.

The spelling of 99988281 in words is "ninety-nine million, nine hundred eighty-eight thousand, two hundred eighty-one".