1211111103 has 4 divisors (see below), whose sum is σ = 1614814808. Its totient is φ = 807407400.

The previous prime is 1211111101. The next prime is 1211111107. The reversal of 1211111103 is 3011111121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3011111121 = 3 ⋅1003703707.

It is not a de Polignac number, because 1211111103 - 2¹ = 1211111101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211111101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201851848 + ... + 201851853.

It is an arithmetic number, because the mean of its divisors is an integer number (403703702).

Almost surely, 2^1211111103 is an apocalyptic number.

1211111103 is a deficient number, since it is larger than the sum of its proper divisors (403703705).

1211111103 is an equidigital number, since it uses as much as digits as its factorization.

1211111103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403703704.

The product of its (nonzero) digits is 6, while the sum is 12.

The square root of 1211111103 is about 34801.0215798330. The cubic root of 1211111103 is about 1065.9283060832.

Adding to 1211111103 its reverse (3011111121), we get a palindrome (4222222224).

The spelling of 1211111103 in words is "one billion, two hundred eleven million, one hundred eleven thousand, one hundred three".