111118561 has 2 divisors, whose sum is σ = 111118562. Its totient is φ = 111118560.

The previous prime is 111118559. The next prime is 111118571. The reversal of 111118561 is 165811111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 100620961 + 10497600 = 10031^2 + 3240^2 .

It is a cyclic number.

It is not a de Polignac number, because 111118561 - 2¹ = 111118559 is a prime.

Together with 111118559, it forms a pair of twin primes.

It is equal to p_6363601 and since 111118561 and 6363601 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (111118541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55559280 + 55559281.

It is an arithmetic number, because the mean of its divisors is an integer number (55559281).

Almost surely, 2^111118561 is an apocalyptic number.

It is an amenable number.

111118561 is a deficient number, since it is larger than the sum of its proper divisors (1).

111118561 is an equidigital number, since it uses as much as digits as its factorization.

111118561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240, while the sum is 25.

The square root of 111118561 is about 10541.2789072294. The cubic root of 111118561 is about 480.7606011281.

Adding to 111118561 its reverse (165811111), we get a palindrome (276929672).

The spelling of 111118561 in words is "one hundred eleven million, one hundred eighteen thousand, five hundred sixty-one".