11561563 has 4 divisors (see below), whose sum is σ = 12450928. Its totient is φ = 10672200.

The previous prime is 11561531. The next prime is 11561591. The reversal of 11561563 is 36516511.

11561563 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36516511 = 197 ⋅185363.

It is a cyclic number.

It is not a de Polignac number, because 11561563 - 2⁵ = 11561531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11561863) 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, 444663 + ... + 444688.

It is an arithmetic number, because the mean of its divisors is an integer number (3112732).

Almost surely, 2^11561563 is an apocalyptic number.

11561563 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

11561563 is a deficient number, since it is larger than the sum of its proper divisors (889365).

11561563 is an equidigital number, since it uses as much as digits as its factorization.

11561563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889364.

The product of its digits is 2700, while the sum is 28.

The square root of 11561563 is about 3400.2298451722. The cubic root of 11561563 is about 226.1199339926.

The spelling of 11561563 in words is "eleven million, five hundred sixty-one thousand, five hundred sixty-three".