111608581 has 16 divisors (see below), whose sum is σ = 134611200. Its totient is φ = 90465408.

The previous prime is 111608579. The next prime is 111608591. The reversal of 111608581 is 185806111.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 111608581 - 2¹ = 111608579 is a prime.

It is a super-2 number, since 2×111608581² = 24912950705667122, which 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 (111608591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10435 + ... + 18223.

It is an arithmetic number, because the mean of its divisors is an integer number (8413200).

Almost surely, 2^111608581 is an apocalyptic number.

It is an amenable number.

111608581 is a deficient number, since it is larger than the sum of its proper divisors (23002619).

111608581 is an equidigital number, since it uses as much as digits as its factorization.

111608581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7908.

The product of its (nonzero) digits is 1920, while the sum is 31.

The square root of 111608581 is about 10564.4962492302. The cubic root of 111608581 is about 481.4662643904.

The spelling of 111608581 in words is "one hundred eleven million, six hundred eight thousand, five hundred eighty-one".