21221000200 has 48 divisors (see below), whose sum is σ = 49462051860. Its totient is φ = 8467200000.

The previous prime is 21221000191. The next prime is 21221000201. The reversal of 21221000200 is 200012212.

It can be written as a sum of positive squares in 6 ways, for example, as 14834752804 + 6386247396 = 121798^2 + 79914^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21221000201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52101 + ... + 212500.

Almost surely, 2^21221000200 is an apocalyptic number.

21221000200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221000200 is an abundant number, since it is smaller than the sum of its proper divisors (28241051660).

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

21221000200 is a wasteful number, since it uses less digits than its factorization.

21221000200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265018 (or 265009 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21221000200 its reverse (200012212), we get a palindrome (21421012412).

The spelling of 21221000200 in words is "twenty-one billion, two hundred twenty-one million, two hundred", and thus it is an aban number.