20111201212111 has 4 divisors (see below), whose sum is σ = 20111484384000. Its totient is φ = 20110918040224.

The previous prime is 20111201212049. The next prime is 20111201212121. The reversal of 20111201212111 is 11121210211102.

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

It is a cyclic number.

It is not a de Polignac number, because 20111201212111 - 2²¹ = 20111199114959 is a prime.

It is a super-2 number, since 2×20111201212111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111201212121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 141479386 + ... + 141621463.

It is an arithmetic number, because the mean of its divisors is an integer number (5027871096000).

Almost surely, 2^{20111201212111} is an apocalyptic number.

20111201212111 is a deficient number, since it is larger than the sum of its proper divisors (283171889).

20111201212111 is an equidigital number, since it uses as much as digits as its factorization.

20111201212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283171888.

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

Adding to 20111201212111 its reverse (11121210211102), we get a palindrome (31232411423213).

The spelling of 20111201212111 in words is "twenty trillion, one hundred eleven billion, two hundred one million, two hundred twelve thousand, one hundred eleven".