99890 has 16 divisors (see below), whose sum is σ = 205632. Its totient is φ = 34224.

The previous prime is 99881. The next prime is 99901. The reversal of 99890 is 9899.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 99890.

It is an unprimeable number.

99890 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 644 + ... + 783.

It is an arithmetic number, because the mean of its divisors is an integer number (12852).

2⁹⁹⁸⁹⁰ is an apocalyptic number.

99890 is an abundant number, since it is smaller than the sum of its proper divisors (105742).

It is a weird number, because it is abundant, but not a pseudoperfect number.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102816).

99890 is a wasteful number, since it uses less digits than its factorization.

99890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1441.

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 99890 is about 316.0537928898. The cubic root of 99890 is about 46.3988629329.

It can be divided in two parts, 99 and 890, that added together give a palindrome (989).

The spelling of 99890 in words is "ninety-nine thousand, eight hundred ninety".