21222700 has 18 divisors (see below), whose sum is σ = 46053476. Its totient is φ = 8489040.

The previous prime is 21222697. The next prime is 21222739. The reversal of 21222700 is 722212.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106014 + ... + 106213.

Almost surely, 2^21222700 is an apocalyptic number.

21222700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222700 is an abundant number, since it is smaller than the sum of its proper divisors (24830776).

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

21222700 is a wasteful number, since it uses less digits than its factorization.

21222700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212241 (or 212234 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 21222700 is about 4606.8101762499. The cubic root of 21222700 is about 276.8642481477.

Adding to 21222700 its reverse (722212), we get a palindrome (21944912).

The spelling of 21222700 in words is "twenty-one million, two hundred twenty-two thousand, seven hundred".