11011111231 has 4 divisors (see below), whose sum is σ = 11052045000. Its totient is φ = 10970177464.

The previous prime is 11011111229. The next prime is 11011111271. The reversal of 11011111231 is 13211111011.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13211111011 = 7 ⋅1887301573.

It is a cyclic number.

It is not a de Polignac number, because 11011111231 - 2¹ = 11011111229 is a prime.

It is a super-2 number, since 2×11011111231² (a number of 21 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 (11011111271) 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, 20466481 + ... + 20467018.

It is an arithmetic number, because the mean of its divisors is an integer number (2763011250).

Almost surely, 2^11011111231 is an apocalyptic number.

11011111231 is a deficient number, since it is larger than the sum of its proper divisors (40933769).

11011111231 is an equidigital number, since it uses as much as digits as its factorization.

11011111231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40933768.

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

Adding to 11011111231 its reverse (13211111011), we get a palindrome (24222222242).

The spelling of 11011111231 in words is "eleven billion, eleven million, one hundred eleven thousand, two hundred thirty-one".