20121010111 has 4 divisors (see below), whose sum is σ = 20143849824. Its totient is φ = 20098170400.

The previous prime is 20121010109. The next prime is 20121010157. The reversal of 20121010111 is 11101012102.

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 20121010111 - 2¹ = 20121010109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11418535 + ... + 11420296.

It is an arithmetic number, because the mean of its divisors is an integer number (5035962456).

Almost surely, 2^20121010111 is an apocalyptic number.

20121010111 is a deficient number, since it is larger than the sum of its proper divisors (22839713).

20121010111 is an equidigital number, since it uses as much as digits as its factorization.

20121010111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22839712.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 20121010111 its reverse (11101012102), we get a palindrome (31222022213).

The spelling of 20121010111 in words is "twenty billion, one hundred twenty-one million, ten thousand, one hundred eleven".