21244412 has 12 divisors (see below), whose sum is σ = 42488880. Its totient is φ = 9104736.

The previous prime is 21244369. The next prime is 21244417. The reversal of 21244412 is 21444212.

21244412 is an admirable number.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244417) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 379337 + ... + 379392.

It is an arithmetic number, because the mean of its divisors is an integer number (3540740).

Almost surely, 2^21244412 is an apocalyptic number.

It is an amenable number.

21244412 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21244412 is a wasteful number, since it uses less digits than its factorization.

21244412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 758740 (or 758738 counting only the distinct ones).

The product of its digits is 512, while the sum is 20.

The square root of 21244412 is about 4609.1660850961. The cubic root of 21244412 is about 276.9586317992.

Adding to 21244412 its reverse (21444212), we get a palindrome (42688624).

The spelling of 21244412 in words is "twenty-one million, two hundred forty-four thousand, four hundred twelve".