115505561 has 4 divisors (see below), whose sum is σ = 115556532. Its totient is φ = 115454592.

The previous prime is 115505501. The next prime is 115505567. The reversal of 115505561 is 165505511.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 58049161 + 57456400 = 7619^2 + 7580^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115505561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (115505567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21920 + ... + 26673.

It is an arithmetic number, because the mean of its divisors is an integer number (28889133).

Almost surely, 2^115505561 is an apocalyptic number.

It is an amenable number.

115505561 is a deficient number, since it is larger than the sum of its proper divisors (50971).

115505561 is an equidigital number, since it uses as much as digits as its factorization.

115505561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50970.

The product of its (nonzero) digits is 3750, while the sum is 29.

The square root of 115505561 is about 10747.3513481229. The cubic root of 115505561 is about 487.0059844073.

The spelling of 115505561 in words is "one hundred fifteen million, five hundred five thousand, five hundred sixty-one".