11643 has 4 divisors (see below), whose sum is σ = 15528. Its totient is φ = 7760.

The previous prime is 11633. The next prime is 11657. The reversal of 11643 is 34611.

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 11643 - 2⁶ = 11579 is a prime.

It is a D-number.

11643 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 11643.

It is not an unprimeable number, because it can be changed into a prime (11633) 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, 1938 + ... + 1943.

It is an arithmetic number, because the mean of its divisors is an integer number (3882).

2¹¹⁶⁴³ is an apocalyptic number.

11643 is a deficient number, since it is larger than the sum of its proper divisors (3885).

11643 is an equidigital number, since it uses as much as digits as its factorization.

11643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3884.

The product of its digits is 72, while the sum is 15.

The square root of 11643 is about 107.9027339783. The cubic root of 11643 is about 22.6649604637.

Subtracting from 11643 its sum of digits (15), we obtain a triangular number (11628 = T₁₅₂).

The spelling of 11643 in words is "eleven thousand, six hundred forty-three".