21484320 has 192 divisors, whose sum is σ = 79761024. Its totient is φ = 4792320.

The previous prime is 21484303. The next prime is 21484321. The reversal of 21484320 is 2348412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21484321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68484 + ... + 68796.

It is an arithmetic number, because the mean of its divisors is an integer number (415422).

Almost surely, 2^21484320 is an apocalyptic number.

21484320 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 21484320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39880512).

21484320 is an abundant number, since it is smaller than the sum of its proper divisors (58276704).

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

21484320 is a wasteful number, since it uses less digits than its factorization.

21484320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 21484320 is about 4635.1181214722. The cubic root of 21484320 is about 277.9972740964.

The spelling of 21484320 in words is "twenty-one million, four hundred eighty-four thousand, three hundred twenty".