99918 has 48 divisors (see below), whose sum is σ = 270816. Its totient is φ = 25920.

The previous prime is 99907. The next prime is 99923. The reversal of 99918 is 81999.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1608 + ... + 1668.

It is an arithmetic number, because the mean of its divisors is an integer number (5642).

2⁹⁹⁹¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135408).

99918 is an abundant number, since it is smaller than the sum of its proper divisors (170898).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99918 is a wasteful number, since it uses less digits than its factorization.

99918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89 (or 86 counting only the distinct ones).

The product of its digits is 5832, while the sum is 36.

The square root of 99918 is about 316.0980860429. The cubic root of 99918 is about 46.4031978573.

It can be divided in two parts, 9991 and 8, that added together give a palindrome (9999).

The spelling of 99918 in words is "ninety-nine thousand, nine hundred eighteen".