11556643 has 4 divisors (see below), whose sum is σ = 13207600. Its totient is φ = 9905688.

The previous prime is 11556641. The next prime is 11556653. The reversal of 11556643 is 34665511.

11556643 is digitally balanced in base 3, 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.

It is a cyclic number.

It is not a de Polignac number, because 11556643 - 2¹ = 11556641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11556641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 825468 + ... + 825481.

It is an arithmetic number, because the mean of its divisors is an integer number (3301900).

Almost surely, 2^11556643 is an apocalyptic number.

11556643 is a deficient number, since it is larger than the sum of its proper divisors (1650957).

11556643 is an equidigital number, since it uses as much as digits as its factorization.

11556643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1650956.

The product of its digits is 10800, while the sum is 31.

The square root of 11556643 is about 3399.5062876836. The cubic root of 11556643 is about 226.0878544799.

The spelling of 11556643 in words is "eleven million, five hundred fifty-six thousand, six hundred forty-three".