21020001012200 has 48 divisors (see below), whose sum is σ = 48873087195660. Its totient is φ = 8407727744000.

The previous prime is 21020001012173. The next prime is 21020001012217. The reversal of 21020001012200 is 221010002012.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 3038042028004 + 17981958984196 = 1742998^2 + 4240514^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4535630 + ... + 7912770.

Almost surely, 2^{21020001012200} is an apocalyptic number.

21020001012200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21020001012200 is an abundant number, since it is smaller than the sum of its proper divisors (27853086183460).

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

21020001012200 is a wasteful number, since it uses less digits than its factorization.

21020001012200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3408278 (or 3408269 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21020001012200 its reverse (221010002012), we get a palindrome (21241011014212).

The spelling of 21020001012200 in words is "twenty-one trillion, twenty billion, one million, twelve thousand, two hundred".