21338226 has 72 divisors (see below), whose sum is σ = 57949164. Its totient is φ = 5624640.

The previous prime is 21338189. The next prime is 21338237. The reversal of 21338226 is 62283312.

It can be written as a sum of positive squares in 2 ways, for example, as 15093225 + 6245001 = 3885^2 + 2499^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21338226.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10536 + ... + 12396.

Almost surely, 2^21338226 is an apocalyptic number.

21338226 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21338226, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28974582).

21338226 is an abundant number, since it is smaller than the sum of its proper divisors (36610938).

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

21338226 is a wasteful number, since it uses less digits than its factorization.

21338226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1896 (or 1886 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 21338226 is about 4619.3317698559. The cubic root of 21338226 is about 277.3657105295.

The spelling of 21338226 in words is "twenty-one million, three hundred thirty-eight thousand, two hundred twenty-six".