111917561 has 8 divisors (see below), whose sum is σ = 128003904. Its totient is φ = 95855760.

The previous prime is 111917551. The next prime is 111917569. The reversal of 111917561 is 165719111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 111917561 - 2²⁶ = 44808697 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (111917569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4991 + ... + 15771.

It is an arithmetic number, because the mean of its divisors is an integer number (16000488).

Almost surely, 2^111917561 is an apocalyptic number.

It is an amenable number.

111917561 is a deficient number, since it is larger than the sum of its proper divisors (16086343).

111917561 is a wasteful number, since it uses less digits than its factorization.

111917561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12271.

The product of its digits is 1890, while the sum is 32.

The square root of 111917561 is about 10579.1096506275. The cubic root of 111917561 is about 481.9101561163.

The spelling of 111917561 in words is "one hundred eleven million, nine hundred seventeen thousand, five hundred sixty-one".