850409 has 4 divisors (see below), whose sum is σ = 971904. Its totient is φ = 728916.

The previous prime is 850403. The next prime is 850417. The reversal of 850409 is 904058.

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 not a de Polignac number, because 850409 - 2⁴ = 850393 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 (850403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60737 + ... + 60750.

It is an arithmetic number, because the mean of its divisors is an integer number (242976).

2⁸⁵⁰⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

850409 is a deficient number, since it is larger than the sum of its proper divisors (121495).

850409 is a wasteful number, since it uses less digits than its factorization.

850409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121494.

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

The square root of 850409 is about 922.1762304462. The cubic root of 850409 is about 94.7420147219.

The spelling of 850409 in words is "eight hundred fifty thousand, four hundred nine".