21480384 has 56 divisors (see below), whose sum is σ = 60185808. Its totient is φ = 6737920.

The previous prime is 21480383. The next prime is 21480391. The reversal of 21480384 is 48308412.

It is a super-2 number, since 2×21480384² = 922813793574912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21480383) 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 7 ways as a sum of consecutive naturals, for example, 27 + ... + 6554.

Almost surely, 2^21480384 is an apocalyptic number.

21480384 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 21480384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30092904).

21480384 is an abundant number, since it is smaller than the sum of its proper divisors (38705424).

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

21480384 is a wasteful number, since it uses less digits than its factorization.

21480384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6613 (or 6603 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 21480384 is about 4634.6935173752. The cubic root of 21480384 is about 277.9802963797.

Adding to 21480384 its reverse (48308412), we get a palindrome (69788796).

The spelling of 21480384 in words is "twenty-one million, four hundred eighty thousand, three hundred eighty-four".