20121120121111 has 4 divisors (see below), whose sum is σ = 20121252541992. Its totient is φ = 20120987700232.

The previous prime is 20121120121051. The next prime is 20121120121121. The reversal of 20121120121111 is 11112102112102.

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 20121120121111 - 2¹⁷ = 20121119990039 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 (20121120121121) 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, 65982256 + ... + 66286501.

It is an arithmetic number, because the mean of its divisors is an integer number (5030313135498).

Almost surely, 2^{20121120121111} is an apocalyptic number.

20121120121111 is a deficient number, since it is larger than the sum of its proper divisors (132420881).

20121120121111 is a wasteful number, since it uses less digits than its factorization.

20121120121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132420880.

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

Adding to 20121120121111 its reverse (11112102112102), we get a palindrome (31233222233213).

The spelling of 20121120121111 in words is "twenty trillion, one hundred twenty-one billion, one hundred twenty million, one hundred twenty-one thousand, one hundred eleven".