20120121111 has 16 divisors (see below), whose sum is σ = 27277941600. Its totient is φ = 13188040320.

The previous prime is 20120121071. The next prime is 20120121137. The reversal of 20120121111 is 11112102102.

It is not a de Polignac number, because 20120121111 - 2¹³ = 20120112919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20120121191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 444901 + ... + 488033.

It is an arithmetic number, because the mean of its divisors is an integer number (1704871350).

Almost surely, 2^20120121111 is an apocalyptic number.

20120121111 is a deficient number, since it is larger than the sum of its proper divisors (7157820489).

20120121111 is a wasteful number, since it uses less digits than its factorization.

20120121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45746.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 20120121111 its reverse (11112102102), we get a palindrome (31232223213).

The spelling of 20120121111 in words is "twenty billion, one hundred twenty million, one hundred twenty-one thousand, one hundred eleven".