21001000200 has 192 divisors, whose sum is σ = 70383144000. Its totient is φ = 5162019840.

The previous prime is 21001000199. The next prime is 21001000213. The reversal of 21001000200 is 200010012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 396906 + ... + 446694.

It is an arithmetic number, because the mean of its divisors is an integer number (366578875).

Almost surely, 2^21001000200 is an apocalyptic number.

21001000200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21001000200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35191572000).

21001000200 is an abundant number, since it is smaller than the sum of its proper divisors (49382143800).

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

21001000200 is a wasteful number, since it uses less digits than its factorization.

21001000200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49864 (or 49855 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

Adding to 21001000200 its reverse (200010012), we get a palindrome (21201010212).

The spelling of 21001000200 in words is "twenty-one billion, one million, two hundred", and thus it is an aban number.