21220300 has 18 divisors (see below), whose sum is σ = 46048268. Its totient is φ = 8488080.

The previous prime is 21220261. The next prime is 21220313. The reversal of 21220300 is 302212.

It is a super-2 number, since 2×21220300² = 900602264180000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

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 5 ways as a sum of consecutive naturals, for example, 106002 + ... + 106201.

Almost surely, 2^21220300 is an apocalyptic number.

21220300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220300 is an abundant number, since it is smaller than the sum of its proper divisors (24827968).

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

21220300 is a wasteful number, since it uses less digits than its factorization.

21220300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212217 (or 212210 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 21220300 is about 4606.5496849594. The cubic root of 21220300 is about 276.8538112217.

Adding to 21220300 its reverse (302212), we get a palindrome (21522512).

The spelling of 21220300 in words is "twenty-one million, two hundred twenty thousand, three hundred".