21322220 has 12 divisors (see below), whose sum is σ = 44776704. Its totient is φ = 8528880.

The previous prime is 21322207. The next prime is 21322229. The reversal of 21322220 is 2222312.

It is a junction number, because it is equal to n+sod(n) for n = 21322195 and 21322204.

It is not an unprimeable number, because it can be changed into a prime (21322229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533036 + ... + 533075.

It is an arithmetic number, because the mean of its divisors is an integer number (3731392).

Almost surely, 2^21322220 is an apocalyptic number.

21322220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21322220 is an abundant number, since it is smaller than the sum of its proper divisors (23454484).

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

21322220 is a wasteful number, since it uses less digits than its factorization.

21322220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066120 (or 1066118 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21322220 is about 4617.5989431738. The cubic root of 21322220 is about 277.2963416566.

Adding to 21322220 its reverse (2222312), we get a palindrome (23544532).

The spelling of 21322220 in words is "twenty-one million, three hundred twenty-two thousand, two hundred twenty".