21973248 has 216 divisors, whose sum is σ = 75300960. Its totient is φ = 6266880.

The previous prime is 21973247. The next prime is 21973261. The reversal of 21973248 is 84237912.

It is a tau number, because it is divible by the number of its divisors (216).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21973247) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1292536 + ... + 1292552.

Almost surely, 2^21973248 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 21973248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37650480).

21973248 is an abundant number, since it is smaller than the sum of its proper divisors (53327712).

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

21973248 is a wasteful number, since it uses less digits than its factorization.

21973248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70 (or 33 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 21973248 is about 4687.5631195750. The cubic root of 21973248 is about 280.0903110041.

It can be divided in two parts, 2197 and 3248, that added together give a palindrome (5445).

The spelling of 21973248 in words is "twenty-one million, nine hundred seventy-three thousand, two hundred forty-eight".