111616391 has 4 divisors (see below), whose sum is σ = 114338784. Its totient is φ = 108894000.

The previous prime is 111616387. The next prime is 111616403. The reversal of 111616391 is 193616111.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 111616391 - 2² = 111616387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111616321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1361135 + ... + 1361216.

It is an arithmetic number, because the mean of its divisors is an integer number (28584696).

Almost surely, 2^111616391 is an apocalyptic number.

111616391 is a deficient number, since it is larger than the sum of its proper divisors (2722393).

111616391 is an equidigital number, since it uses as much as digits as its factorization.

111616391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2722392.

The product of its digits is 972, while the sum is 29.

The square root of 111616391 is about 10564.8658770474. The cubic root of 111616391 is about 481.4774946016.

The spelling of 111616391 in words is "one hundred eleven million, six hundred sixteen thousand, three hundred ninety-one".