21384160 has 96 divisors (see below), whose sum is σ = 58871232. Its totient is φ = 7188480.

The previous prime is 21384151. The next prime is 21384161. The reversal of 21384160 is 6148312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21384161) 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 15 ways as a sum of consecutive naturals, for example, 68164 + ... + 68476.

It is an arithmetic number, because the mean of its divisors is an integer number (613242).

Almost surely, 2^21384160 is an apocalyptic number.

21384160 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 21384160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29435616).

21384160 is an abundant number, since it is smaller than the sum of its proper divisors (37487072).

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

21384160 is a wasteful number, since it uses less digits than its factorization.

21384160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 21384160 is about 4624.3010282636. The cubic root of 21384160 is about 277.5645928149.

The spelling of 21384160 in words is "twenty-one million, three hundred eighty-four thousand, one hundred sixty".