845009 has 4 divisors (see below), whose sum is σ = 921840. Its totient is φ = 768180.

The previous prime is 845003. The next prime is 845017. The reversal of 845009 is 900548.

845009 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-845009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (845003) 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, 38399 + ... + 38420.

It is an arithmetic number, because the mean of its divisors is an integer number (230460).

2⁸⁴⁵⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

845009 is a deficient number, since it is larger than the sum of its proper divisors (76831).

845009 is a wasteful number, since it uses less digits than its factorization.

845009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76830.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 845009 is about 919.2437108841. The cubic root of 845009 is about 94.5410551062.

The spelling of 845009 in words is "eight hundred forty-five thousand, nine".