21301344 has 72 divisors (see below), whose sum is σ = 62244000. Its totient is φ = 6905088.

The previous prime is 21301339. The next prime is 21301361. The reversal of 21301344 is 44310312.

21301344 is a `hidden beast` number, since 21 + 301 + 344 = 666.

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

It is a Harshad number since it is a multiple of its sum of digits (18).

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 11 ways as a sum of consecutive naturals, for example, 9657 + ... + 11655.

It is an arithmetic number, because the mean of its divisors is an integer number (864500).

Almost surely, 2^21301344 is an apocalyptic number.

21301344 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 21301344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31122000).

21301344 is an abundant number, since it is smaller than the sum of its proper divisors (40942656).

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

21301344 is a wasteful number, since it uses less digits than its factorization.

21301344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2052 (or 2041 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 21301344 is about 4615.3379074560. The cubic root of 21301344 is about 277.2058143618.

Adding to 21301344 its reverse (44310312), we get a palindrome (65611656).

The spelling of 21301344 in words is "twenty-one million, three hundred one thousand, three hundred forty-four".