20011011111 has 48 divisors (see below), whose sum is σ = 35602432320. Its totient is φ = 10547159040.

The previous prime is 20011011073. The next prime is 20011011113. The reversal of 20011011111 is 11111011002.

It is not a de Polignac number, because 20011011111 - 2⁷ = 20011010983 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 = 20011011093 and 20011011102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011011113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1145301 + ... + 1162641.

It is an arithmetic number, because the mean of its divisors is an integer number (741717340).

Almost surely, 2^20011011111 is an apocalyptic number.

20011011111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20011011111 is a deficient number, since it is larger than the sum of its proper divisors (15591421209).

20011011111 is a wasteful number, since it uses less digits than its factorization.

20011011111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18776 (or 18773 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 20011011111 its reverse (11111011002), we get a palindrome (31122022113).

The spelling of 20011011111 in words is "twenty billion, eleven million, eleven thousand, one hundred eleven".