20101200111 has 8 divisors (see below), whose sum is σ = 29779555760. Its totient is φ = 13400800056.

The previous prime is 20101200107. The next prime is 20101200137. The reversal of 20101200111 is 11100210102.

It is a happy number.

It is not a de Polignac number, because 20101200111 - 2² = 20101200107 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20101200093 and 20101200102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101200101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 372244420 + ... + 372244473.

It is an arithmetic number, because the mean of its divisors is an integer number (3722444470).

Almost surely, 2^20101200111 is an apocalyptic number.

20101200111 is a deficient number, since it is larger than the sum of its proper divisors (9678355649).

20101200111 is an equidigital number, since it uses as much as digits as its factorization.

20101200111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744488902 (or 744488896 counting only the distinct ones).

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

Adding to 20101200111 its reverse (11100210102), we get a palindrome (31201410213).

Subtracting from 20101200111 its reverse (11100210102), we obtain a palindrome (9000990009).

The spelling of 20101200111 in words is "twenty billion, one hundred one million, two hundred thousand, one hundred eleven".