21384198 has 48 divisors (see below), whose sum is σ = 53526096. Its totient is φ = 6097920.

The previous prime is 21384179. The next prime is 21384229. The reversal of 21384198 is 89148312.

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, 190 + ... + 6542.

It is an arithmetic number, because the mean of its divisors is an integer number (1115127).

Almost surely, 2^21384198 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21384198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26763048).

21384198 is an abundant number, since it is smaller than the sum of its proper divisors (32141898).

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

21384198 is a wasteful number, since it uses less digits than its factorization.

21384198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6389 (or 6386 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 21384198 is about 4624.3051369909. The cubic root of 21384198 is about 277.5647572270.

It can be divided in two parts, 2138 and 4198, that added together give a palindrome (6336).

The spelling of 21384198 in words is "twenty-one million, three hundred eighty-four thousand, one hundred ninety-eight".