20101011111 has 20 divisors (see below), whose sum is σ = 30153103200. Its totient is φ = 13344591456.

The previous prime is 20101011109. The next prime is 20101011113. The reversal of 20101011111 is 11111010102.

It is an interprime number because it is at equal distance from previous prime (20101011109) and next prime (20101011113).

It is not a de Polignac number, because 20101011111 - 2¹ = 20101011109 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 = 20101011093 and 20101011102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101011113) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 499806 + ... + 538523.

It is an arithmetic number, because the mean of its divisors is an integer number (1507655160).

Almost surely, 2^20101011111 is an apocalyptic number.

20101011111 is a deficient number, since it is larger than the sum of its proper divisors (10052092089).

20101011111 is a wasteful number, since it uses less digits than its factorization.

20101011111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1038580 (or 1038571 counting only the distinct ones).

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

Adding to 20101011111 its reverse (11111010102), we get a palindrome (31212021213).

The spelling of 20101011111 in words is "twenty billion, one hundred one million, eleven thousand, one hundred eleven".