21241944 has 72 divisors (see below), whose sum is σ = 59639580. Its totient is φ = 6829920.

The previous prime is 21241939. The next prime is 21241951. The reversal of 21241944 is 44914212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 69039 + ... + 69345.

Almost surely, 2^21241944 is an apocalyptic number.

21241944 is a gapful number since it is divisible by the number (24) 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 21241944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29819790).

21241944 is an abundant number, since it is smaller than the sum of its proper divisors (38397636).

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

21241944 is a wasteful number, since it uses less digits than its factorization.

21241944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 343 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21241944 is about 4608.8983499314. The cubic root of 21241944 is about 276.9479064631.

The spelling of 21241944 in words is "twenty-one million, two hundred forty-one thousand, nine hundred forty-four".