11311111 has 12 divisors (see below), whose sum is σ = 13215792. Its totient is φ = 9680832.

The previous prime is 11311109. The next prime is 11311117. The reversal of 11311111 is 11111311.

It is not a de Polignac number, because 11311111 - 2¹ = 11311109 is a prime.

It is a Duffinian number.

11311111 is a modest number, since divided by 11111 gives 113 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11311117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16471 + ... + 17143.

It is an arithmetic number, because the mean of its divisors is an integer number (1101316).

Almost surely, 2^11311111 is an apocalyptic number.

11311111 is a deficient number, since it is larger than the sum of its proper divisors (1904681).

11311111 is an frugal number, since it uses more digits than its factorization.

11311111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 708 (or 680 counting only the distinct ones).

The product of its digits is 3, while the sum is 10.

The square root of 11311111 is about 3363.1995183159. The cubic root of 11311111 is about 224.4752280443.

Adding to 11311111 its reverse (11111311), we get a palindrome (22422422).

It can be divided in two parts, 11311 and 111, that multiplied together give a palindrome (1255521).

The spelling of 11311111 in words is "eleven million, three hundred eleven thousand, one hundred eleven".