111231001018 has 4 divisors (see below), whose sum is σ = 166846501530. Its totient is φ = 55615500508.

The previous prime is 111231000989. The next prime is 111231001019. The reversal of 111231001018 is 810100132111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 810100132111 = 359 ⋅2256546329.

It can be written as a sum of positive squares in only one way, i.e., 102331531449 + 8899469569 = 319893^2 + 94337^2 .

It is a junction number, because it is equal to n+sod(n) for n = 111231000986 and 111231001004.

It is not an unprimeable number, because it can be changed into a prime (111231001019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27807750253 + ... + 27807750256.

Almost surely, 2^111231001018 is an apocalyptic number.

111231001018 is a deficient number, since it is larger than the sum of its proper divisors (55615500512).

111231001018 is an equidigital number, since it uses as much as digits as its factorization.

111231001018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55615500511.

The product of its (nonzero) digits is 48, while the sum is 19.

Adding to 111231001018 its reverse (810100132111), we get a palindrome (921331133129).

The spelling of 111231001018 in words is "one hundred eleven billion, two hundred thirty-one million, one thousand, eighteen".