20001102101221 has 4 divisors (see below), whose sum is σ = 20158591094272. Its totient is φ = 19843613108172.

The previous prime is 20001102101219. The next prime is 20001102101327. The reversal of 20001102101221 is 12210120110002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20001102101221 - 2¹ = 20001102101219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001102101621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78744496335 + ... + 78744496588.

It is an arithmetic number, because the mean of its divisors is an integer number (5039647773568).

Almost surely, 2^{20001102101221} is an apocalyptic number.

It is an amenable number.

20001102101221 is a deficient number, since it is larger than the sum of its proper divisors (157488993051).

20001102101221 is a wasteful number, since it uses less digits than its factorization.

20001102101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157488993050.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20001102101221 its reverse (12210120110002), we get a palindrome (32211222211223).

The spelling of 20001102101221 in words is "twenty trillion, one billion, one hundred two million, one hundred one thousand, two hundred twenty-one".