1211100111103 has 4 divisors (see below), whose sum is σ = 1211105621008. Its totient is φ = 1211094601200.

The previous prime is 1211100111097. The next prime is 1211100111107. The reversal of 1211100111103 is 3011110011121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1211100111103 - 2¹³ = 1211100102911 is a prime.

It is a super-2 number, since 2×1211100111103² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211100111107) 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 3 ways as a sum of consecutive naturals, for example, 2410926 + ... + 2869627.

It is an arithmetic number, because the mean of its divisors is an integer number (302776405252).

Almost surely, 2^{1211100111103} is an apocalyptic number.

1211100111103 is a deficient number, since it is larger than the sum of its proper divisors (5509905).

1211100111103 is an equidigital number, since it uses as much as digits as its factorization.

1211100111103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5509904.

The product of its (nonzero) digits is 6, while the sum is 13.

Adding to 1211100111103 its reverse (3011110011121), we get a palindrome (4222210122224).

The spelling of 1211100111103 in words is "one trillion, two hundred eleven billion, one hundred million, one hundred eleven thousand, one hundred three".