21384000 has 336 divisors, whose sum is σ = 86538816. Its totient is φ = 5184000.

The previous prime is 21383969. The next prime is 21384061. The reversal of 21384000 is 48312.

It is a happy number.

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 polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1943995 + ... + 1944005.

It is an arithmetic number, because the mean of its divisors is an integer number (257556).

Almost surely, 2^21384000 is an apocalyptic number.

21384000 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 21384000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43269408).

21384000 is an abundant number, since it is smaller than the sum of its proper divisors (65154816).

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

21384000 is an equidigital number, since it uses as much as digits as its factorization.

21384000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 21384000 is about 4624.2837283194. The cubic root of 21384000 is about 277.5639005510.

The spelling of 21384000 in words is "twenty-one million, three hundred eighty-four thousand".