21022250 has 16 divisors (see below), whose sum is σ = 39354120. Its totient is φ = 8408800.

The previous prime is 21022249. The next prime is 21022259. The reversal of 21022250 is 5222012.

It can be written as a sum of positive squares in 4 ways, for example, as 7546009 + 13476241 = 2747^2 + 3671^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21022259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41795 + ... + 42294.

Almost surely, 2^21022250 is an apocalyptic number.

21022250 is a deficient number, since it is larger than the sum of its proper divisors (18331870).

21022250 is an equidigital number, since it uses as much as digits as its factorization.

21022250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84106 (or 84096 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 21022250 is about 4585.0027262805. The cubic root of 21022250 is about 275.9898214408.

Adding to 21022250 its reverse (5222012), we get a palindrome (26244262).

The spelling of 21022250 in words is "twenty-one million, twenty-two thousand, two hundred fifty".