20112111 has 8 divisors (see below), whose sum is σ = 29795760. Its totient is φ = 13408056.

The previous prime is 20112107. The next prime is 20112119. The reversal of 20112111 is 11121102.

It is a happy number.

It is not a de Polignac number, because 20112111 - 2² = 20112107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 20112093 and 20112102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112119) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 372420 + ... + 372473.

It is an arithmetic number, because the mean of its divisors is an integer number (3724470).

Almost surely, 2^20112111 is an apocalyptic number.

20112111 is a deficient number, since it is larger than the sum of its proper divisors (9683649).

20112111 is an equidigital number, since it uses as much as digits as its factorization.

20112111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744902 (or 744896 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 20112111 is about 4484.6528293726. The cubic root of 20112111 is about 271.9480103561.

Adding to 20112111 its reverse (11121102), we get a palindrome (31233213).

The spelling of 20112111 in words is "twenty million, one hundred twelve thousand, one hundred eleven".