21000200101221 has 16 divisors (see below), whose sum is σ = 30547247376960. Its totient is φ = 12726768261120.

The previous prime is 21000200101211. The next prime is 21000200101247. The reversal of 21000200101221 is 12210100200012.

It is not a de Polignac number, because 21000200101221 - 2⁵ = 21000200101189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000200101197 and 21000200101206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000200101211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14961666 + ... + 16304963.

It is an arithmetic number, because the mean of its divisors is an integer number (1909202961060).

Almost surely, 2^{21000200101221} is an apocalyptic number.

It is an amenable number.

21000200101221 is a deficient number, since it is larger than the sum of its proper divisors (9547047275739).

21000200101221 is a wasteful number, since it uses less digits than its factorization.

21000200101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31286996.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000200101221 its reverse (12210100200012), we get a palindrome (33210300301233).

The spelling of 21000200101221 in words is "twenty-one trillion, two hundred million, one hundred one thousand, two hundred twenty-one".