21448288 has 48 divisors (see below), whose sum is σ = 45314640. Its totient is φ = 9957376.

The previous prime is 21448267. The next prime is 21448291. The reversal of 21448288 is 88284412.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48195 + ... + 48637.

It is an arithmetic number, because the mean of its divisors is an integer number (944055).

Almost surely, 2^21448288 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21448288, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22657320).

21448288 is an abundant number, since it is smaller than the sum of its proper divisors (23866352).

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

21448288 is a wasteful number, since it uses less digits than its factorization.

21448288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559 (or 551 counting only the distinct ones).

The product of its digits is 32768, while the sum is 37.

The square root of 21448288 is about 4631.2296423304. The cubic root of 21448288 is about 277.8417745999.

It can be divided in two parts, 21448 and 288, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 21448288 in words is "twenty-one million, four hundred forty-eight thousand, two hundred eighty-eight".