21244300 has 144 divisors (see below), whose sum is σ = 59996160. Its totient is φ = 6336000.

The previous prime is 21244291. The next prime is 21244303. The reversal of 21244300 is 344212.

21244300 = T₇₀₄ + T₇₀₅ + ... + T₇₈₀.

It is not an unprimeable number, because it can be changed into a prime (21244303) 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, 238656 + ... + 238744.

It is an arithmetic number, because the mean of its divisors is an integer number (416640).

Almost surely, 2^21244300 is an apocalyptic number.

21244300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21244300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29998080).

21244300 is an abundant number, since it is smaller than the sum of its proper divisors (38751860).

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

21244300 is a wasteful number, since it uses less digits than its factorization.

21244300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 145 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21244300 is about 4609.1539353769. The cubic root of 21244300 is about 276.9581450920.

Adding to 21244300 its reverse (344212), we get a palindrome (21588512).

The spelling of 21244300 in words is "twenty-one million, two hundred forty-four thousand, three hundred".