4005689 has 4 divisors (see below), whose sum is σ = 4010640. Its totient is φ = 4000740.

The previous prime is 4005653. The next prime is 4005691. The reversal of 4005689 is 9865004.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 4005689 - 2⁸ = 4005433 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (4005619) 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, 947 + ... + 2984.

It is an arithmetic number, because the mean of its divisors is an integer number (1002660).

Almost surely, 2^4005689 is an apocalyptic number.

It is an amenable number.

4005689 is a deficient number, since it is larger than the sum of its proper divisors (4951).

4005689 is a wasteful number, since it uses less digits than its factorization.

4005689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4950.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 4005689 is about 2001.4217446605. The cubic root of 4005689 is about 158.8153255856.

The spelling of 4005689 in words is "four million, five thousand, six hundred eighty-nine".