809680 has 40 divisors (see below), whose sum is σ = 1953000. Its totient is φ = 311808.

The previous prime is 809629. The next prime is 809701. The reversal of 809680 is 86908.

It can be written as a sum of positive squares in 4 ways, for example, as 156816 + 652864 = 396^2 + 808^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2146 + ... + 2494.

It is an arithmetic number, because the mean of its divisors is an integer number (48825).

2⁸⁰⁹⁶⁸⁰ is an apocalyptic number.

809680 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 809680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (976500).

809680 is an abundant number, since it is smaller than the sum of its proper divisors (1143320).

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

809680 is a wasteful number, since it uses less digits than its factorization.

809680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 385 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 809680 is about 899.8222046605. The cubic root of 809680 is about 93.2046980753.

It can be divided in two parts, 80 and 9680, that multiplied together give a square (774400 = 880²).

The spelling of 809680 in words is "eight hundred nine thousand, six hundred eighty".