21044250 has 96 divisors (see below), whose sum is σ = 58406400. Its totient is φ = 5464800.

The previous prime is 21044237. The next prime is 21044251. The reversal of 21044250 is 5244012.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21044251) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 105651 + ... + 105849.

It is an arithmetic number, because the mean of its divisors is an integer number (608400).

Almost surely, 2^21044250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21044250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29203200).

21044250 is an abundant number, since it is smaller than the sum of its proper divisors (37362150).

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

21044250 is a wasteful number, since it uses less digits than its factorization.

21044250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269 (or 256 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 21044250 is about 4587.4012250947. The cubic root of 21044250 is about 276.0860632678.

Adding to 21044250 its reverse (5244012), we get a palindrome (26288262).

The spelling of 21044250 in words is "twenty-one million, forty-four thousand, two hundred fifty".