1186561 has 4 divisors (see below), whose sum is σ = 1196032. Its totient is φ = 1177092.

The previous prime is 1186541. The next prime is 1186573. The reversal of 1186561 is 1656811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1656811 = 13 ⋅127447.

It is a cyclic number.

It is not a de Polignac number, because 1186561 - 2⁹ = 1186049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1186541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4545 + ... + 4798.

It is an arithmetic number, because the mean of its divisors is an integer number (299008).

2^1186561 is an apocalyptic number.

It is an amenable number.

1186561 is a deficient number, since it is larger than the sum of its proper divisors (9471).

1186561 is an equidigital number, since it uses as much as digits as its factorization.

1186561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9470.

The product of its digits is 1440, while the sum is 28.

The square root of 1186561 is about 1089.2938079325. The cubic root of 1186561 is about 105.8676703981.

The spelling of 1186561 in words is "one million, one hundred eighty-six thousand, five hundred sixty-one".