805423644 has 72 divisors (see below), whose sum is σ = 2074887360. Its totient is φ = 263382912.

The previous prime is 805423643. The next prime is 805423657. The reversal of 805423644 is 446324508.

805423644 is a `hidden beast` number, since 8 + 0 + 5 + 4 + 2 + 3 + 644 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 805423599 and 805423608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805423643) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 491194 + ... + 492830.

It is an arithmetic number, because the mean of its divisors is an integer number (28817880).

Almost surely, 2^805423644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 805423644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1037443680).

805423644 is an abundant number, since it is smaller than the sum of its proper divisors (1269463716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

805423644 is a wasteful number, since it uses less digits than its factorization.

805423644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1899 (or 1894 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 36.

The square root of 805423644 is about 28379.9866807580. The cubic root of 805423644 is about 930.4109040972.

The spelling of 805423644 in words is "eight hundred five million, four hundred twenty-three thousand, six hundred forty-four".