21763072 has 44 divisors (see below), whose sum is σ = 44436276. Its totient is φ = 10649600.

The previous prime is 21763069. The next prime is 21763073. The reversal of 21763072 is 27036712.

It can be written as a sum of positive squares in 2 ways, for example, as 19501056 + 2262016 = 4416^2 + 1504^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21763072.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21763073) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54072 + ... + 54472.

Almost surely, 2^21763072 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 21763072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22218138).

21763072 is an abundant number, since it is smaller than the sum of its proper divisors (22673204).

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

21763072 is an equidigital number, since it uses as much as digits as its factorization.

21763072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474 (or 456 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 21763072 is about 4665.0907815390. The cubic root of 21763072 is about 279.1944192008.

Adding to 21763072 its reverse (27036712), we get a palindrome (48799784).

The spelling of 21763072 in words is "twenty-one million, seven hundred sixty-three thousand, seventy-two".