20001000101221 has 12 divisors (see below), whose sum is σ = 20770617719020. Its totient is φ = 19254537812160.

The previous prime is 20001000101213. The next prime is 20001000101233. The reversal of 20001000101221 is 12210100010002.

It can be written as a sum of positive squares in 2 ways, for example, as 3486846636100 + 16514153465121 = 1867310^2 + 4063761^2 .

It is not a de Polignac number, because 20001000101221 - 2³ = 20001000101213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20001000101198 and 20001000101207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001000101021) 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, 74081016 + ... + 74350513.

Almost surely, 2^{20001000101221} is an apocalyptic number.

It is an amenable number.

20001000101221 is a deficient number, since it is larger than the sum of its proper divisors (769617617799).

20001000101221 is an equidigital number, since it uses as much as digits as its factorization.

20001000101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148431684 (or 148431637 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20001000101221 its reverse (12210100010002), we get a palindrome (32211100111223).

The spelling of 20001000101221 in words is "twenty trillion, one billion, one hundred one thousand, two hundred twenty-one".