21044000 has 48 divisors (see below), whose sum is σ = 51714936. Its totient is φ = 8416000.

The previous prime is 21043999. The next prime is 21044003. The reversal of 21044000 is 44012.

It can be written as a sum of positive squares in 4 ways, for example, as 8737936 + 12306064 = 2956^2 + 3508^2 .

It is not an unprimeable number, because it can be changed into a prime (21044003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1370 + ... + 6630.

Almost surely, 2^21044000 is an apocalyptic number.

21044000 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 21044000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25857468).

21044000 is an abundant number, since it is smaller than the sum of its proper divisors (30670936).

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

21044000 is an equidigital number, since it uses as much as digits as its factorization.

21044000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5286 (or 5268 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 21044000 is about 4587.3739764706. The cubic root of 21044000 is about 276.0849699875.

Adding to 21044000 its reverse (44012), we get a palindrome (21088012).

The spelling of 21044000 in words is "twenty-one million, forty-four thousand".