809445 has 32 divisors (see below), whose sum is σ = 1596672. Its totient is φ = 340992.

The previous prime is 809443. The next prime is 809447. The reversal of 809445 is 544908.

It is an interprime number because it is at equal distance from previous prime (809443) and next prime (809447).

It is not a de Polignac number, because 809445 - 2¹ = 809443 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809443) 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 31 ways as a sum of consecutive naturals, for example, 1069 + ... + 1661.

It is an arithmetic number, because the mean of its divisors is an integer number (49896).

2⁸⁰⁹⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

809445 is a deficient number, since it is larger than the sum of its proper divisors (787227).

809445 is a wasteful number, since it uses less digits than its factorization.

809445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 809445 is about 899.6916138322. The cubic root of 809445 is about 93.1956800174.

The spelling of 809445 in words is "eight hundred nine thousand, four hundred forty-five".