21110228 has 12 divisors (see below), whose sum is σ = 38549280. Its totient is φ = 10096152.

The previous prime is 21110227. The next prime is 21110233. The reversal of 21110228 is 82201112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110227) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 114638 + ... + 114821.

It is an arithmetic number, because the mean of its divisors is an integer number (3212440).

Almost surely, 2^21110228 is an apocalyptic number.

It is an amenable number.

21110228 is a deficient number, since it is larger than the sum of its proper divisors (17439052).

21110228 is a wasteful number, since it uses less digits than its factorization.

21110228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229486 (or 229484 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 21110228 is about 4594.5868149378. The cubic root of 21110228 is about 276.3742908965.

The spelling of 21110228 in words is "twenty-one million, one hundred ten thousand, two hundred twenty-eight".