20001101221001 has 2 divisors, whose sum is σ = 20001101221002. Its totient is φ = 20001101221000.

The previous prime is 20001101220973. The next prime is 20001101221067. The reversal of 20001101221001 is 10012210110002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15154164337225 + 4846936883776 = 3892835^2 + 2201576^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20001101221001 is a prime.

It is not a weakly prime, because it can be changed into another prime (20001101221301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000550610500 + 10000550610501.

It is an arithmetic number, because the mean of its divisors is an integer number (10000550610501).

Almost surely, 2^{20001101221001} is an apocalyptic number.

It is an amenable number.

20001101221001 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001101221001 is an equidigital number, since it uses as much as digits as its factorization.

20001101221001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 20001101221001 its reverse (10012210110002), we get a palindrome (30013311331003).

The spelling of 20001101221001 in words is "twenty trillion, one billion, one hundred one million, two hundred twenty-one thousand, one".