21248000 has 96 divisors (see below), whose sum is σ = 53660880. Its totient is φ = 8396800.

The previous prime is 21247999. The next prime is 21248009. The reversal of 21248000 is 84212.

It is a self number, because there is not a number n which added to its sum of digits gives 21248000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21248009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255959 + ... + 256041.

Almost surely, 2^21248000 is an apocalyptic number.

21248000 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 21248000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26830440).

21248000 is an abundant number, since it is smaller than the sum of its proper divisors (32412880).

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

21248000 is an frugal number, since it uses more digits than its factorization.

21248000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 21248000 is about 4609.5552930841. Note that the first 3 decimals coincide. The cubic root of 21248000 is about 276.9742229051.

The spelling of 21248000 in words is "twenty-one million, two hundred forty-eight thousand".