109890 has 64 divisors (see below), whose sum is σ = 328320. Its totient is φ = 25920.

The previous prime is 109883. The next prime is 109891. The reversal of 109890 is 98901.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (109891) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2952 + ... + 2988.

It is an arithmetic number, because the mean of its divisors is an integer number (5130).

2¹⁰⁹⁸⁹⁰ is an apocalyptic number.

109890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 109890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (164160).

109890 is an abundant number, since it is smaller than the sum of its proper divisors (218430).

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

109890 is a wasteful number, since it uses less digits than its factorization.

109890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 109890 is about 331.4966063175. The cubic root of 109890 is about 47.8982218443.

It can be divided in two parts, 109 and 890, that added together give a palindrome (999).

The spelling of 109890 in words is "one hundred nine thousand, eight hundred ninety".