21044100 has 144 divisors (see below), whose sum is σ = 75995136. Its totient is φ = 4368000.

The previous prime is 21044081. The next prime is 21044117. The reversal of 21044100 is 144012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22645 + ... + 23555.

It is an arithmetic number, because the mean of its divisors is an integer number (527744).

Almost surely, 2^21044100 is an apocalyptic number.

21044100 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 21044100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37997568).

21044100 is an abundant number, since it is smaller than the sum of its proper divisors (54951036).

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

21044100 is a wasteful number, since it uses less digits than its factorization.

21044100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 946 (or 939 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21044100 is about 4587.3848759397. The cubic root of 21044100 is about 276.0854073007.

Adding to 21044100 its reverse (144012), we get a palindrome (21188112).

It can be divided in two parts, 210 and 44100, that multiplied together give a cube (9261000 = 210³).

The spelling of 21044100 in words is "twenty-one million, forty-four thousand, one hundred".