11111320231 has 16 divisors (see below), whose sum is σ = 12214116000. Its totient is φ = 10024099200.

The previous prime is 11111320229. The next prime is 11111320247. The reversal of 11111320231 is 13202311111.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 11111320231 - 2¹ = 11111320229 is a prime.

It is a super-2 number, since 2×11111320231² (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 (11111320201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2261005 + ... + 2265913.

It is an arithmetic number, because the mean of its divisors is an integer number (763382250).

Almost surely, 2^11111320231 is an apocalyptic number.

11111320231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11111320231 is a deficient number, since it is larger than the sum of its proper divisors (1102795769).

11111320231 is a wasteful number, since it uses less digits than its factorization.

11111320231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6450.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 11111320231 its reverse (13202311111), we get a palindrome (24313631342).

It can be divided in two parts, 1111 and 1320231, that multiplied together give a palindrome (1466776641).

The spelling of 11111320231 in words is "eleven billion, one hundred eleven million, three hundred twenty thousand, two hundred thirty-one".