21226842 has 48 divisors (see below), whose sum is σ = 56609280. Its totient is φ = 5597856.

The previous prime is 21226837. The next prime is 21226853. The reversal of 21226842 is 24862212.

It is a happy number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 4842 + ... + 8117.

It is an arithmetic number, because the mean of its divisors is an integer number (1179360).

Almost surely, 2^21226842 is an apocalyptic number.

21226842 is an abundant number, since it is smaller than the sum of its proper divisors (35382438).

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

21226842 is a wasteful number, since it uses less digits than its factorization.

21226842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12987 (or 12984 counting only the distinct ones).

The product of its digits is 3072, while the sum is 27.

The square root of 21226842 is about 4607.2597061594. The cubic root of 21226842 is about 276.8822586917.

The spelling of 21226842 in words is "twenty-one million, two hundred twenty-six thousand, eight hundred forty-two".