21480000 has 140 divisors (see below), whose sum is σ = 71414640. Its totient is φ = 5696000.

The previous prime is 21479963. The next prime is 21480001. The reversal of 21480000 is 8412.

It is a super-2 number, since 2×21480000² = 922780800000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (21480001) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 119911 + ... + 120089.

Almost surely, 2^21480000 is an apocalyptic number.

21480000 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 21480000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35707320).

21480000 is an abundant number, since it is smaller than the sum of its proper divisors (49934640).

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

21480000 is an equidigital number, since it uses as much as digits as its factorization.

21480000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 189 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 21480000 is about 4634.6520905026. The cubic root of 21480000 is about 277.9786399060.

Adding to 21480000 its reverse (8412), we get a palindrome (21488412).

The spelling of 21480000 in words is "twenty-one million, four hundred eighty thousand".