21221022 has 8 divisors (see below), whose sum is σ = 42442056. Its totient is φ = 7073672.

The previous prime is 21221021. The next prime is 21221033. The reversal of 21221022 is 22012212.

It is a sphenic number, since it is the product of 3 distinct primes.

21221022 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21220989 and 21221007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221021) 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, 1768413 + ... + 1768424.

It is an arithmetic number, because the mean of its divisors is an integer number (5305257).

Almost surely, 2^21221022 is an apocalyptic number.

21221022 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21221022 is a wasteful number, since it uses less digits than its factorization.

21221022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3536842.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21221022 is about 4606.6280509718. The cubic root of 21221022 is about 276.8569510797.

Adding to 21221022 its reverse (22012212), we get a palindrome (43233234).

The spelling of 21221022 in words is "twenty-one million, two hundred twenty-one thousand, twenty-two".