20101220122111 has 4 divisors (see below), whose sum is σ = 20528905656672. Its totient is φ = 19673534587552.

The previous prime is 20101220122099. The next prime is 20101220122133. The reversal of 20101220122111 is 11122102210102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20101220122111 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 (20101220125111) 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, 213842767210 + ... + 213842767303.

It is an arithmetic number, because the mean of its divisors is an integer number (5132226414168).

Almost surely, 2^{20101220122111} is an apocalyptic number.

20101220122111 is a deficient number, since it is larger than the sum of its proper divisors (427685534561).

20101220122111 is an equidigital number, since it uses as much as digits as its factorization.

20101220122111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427685534560.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 20101220122111 its reverse (11122102210102), we get a palindrome (31223322332213).

The spelling of 20101220122111 in words is "twenty trillion, one hundred one billion, two hundred twenty million, one hundred twenty-two thousand, one hundred eleven".