21223250 has 32 divisors (see below), whose sum is σ = 41468544. Its totient is φ = 8118000.

The previous prime is 21223219. The next prime is 21223261. The reversal of 21223250 is 5232212.

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 15 ways as a sum of consecutive naturals, for example, 3905 + ... + 7595.

It is an arithmetic number, because the mean of its divisors is an integer number (1295892).

Almost surely, 2^21223250 is an apocalyptic number.

21223250 is a deficient number, since it is larger than the sum of its proper divisors (20245294).

21223250 is a wasteful number, since it uses less digits than its factorization.

21223250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3731 (or 3721 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 21223250 is about 4606.8698700962. The cubic root of 21223250 is about 276.8666398324.

Adding to 21223250 its reverse (5232212), we get a palindrome (26455462).

The spelling of 21223250 in words is "twenty-one million, two hundred twenty-three thousand, two hundred fifty".