21822084 has 72 divisors (see below), whose sum is σ = 59026968. Its totient is φ = 6773760.

The previous prime is 21822083. The next prime is 21822103. The reversal of 21822084 is 48022812.

It can be written as a sum of positive squares in 4 ways, for example, as 5419584 + 16402500 = 2328^2 + 4050^2 .

It is not an unprimeable number, because it can be changed into a prime (21822083) 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, 110674 + ... + 110870.

It is an arithmetic number, because the mean of its divisors is an integer number (819819).

Almost surely, 2^21822084 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 21822084, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29513484).

21822084 is an abundant number, since it is smaller than the sum of its proper divisors (37204884).

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

21822084 is a wasteful number, since it uses less digits than its factorization.

21822084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 21822084 is about 4671.4113499027. The cubic root of 21822084 is about 279.4465427935.

Adding to 21822084 its reverse (48022812), we get a palindrome (69844896).

The spelling of 21822084 in words is "twenty-one million, eight hundred twenty-two thousand, eighty-four".