805520 has 20 divisors (see below), whose sum is σ = 1873020. Its totient is φ = 322176.

The previous prime is 805517. The next prime is 805523. The reversal of 805520 is 25508.

It is an interprime number because it is at equal distance from previous prime (805517) and next prime (805523).

It can be written as a sum of positive squares in 2 ways, for example, as 246016 + 559504 = 496^2 + 748^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 805492 and 805501.

It is not an unprimeable number, because it can be changed into a prime (805523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4955 + ... + 5114.

It is an arithmetic number, because the mean of its divisors is an integer number (93651).

2⁸⁰⁵⁵²⁰ is an apocalyptic number.

805520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

805520 is an abundant number, since it is smaller than the sum of its proper divisors (1067500).

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

805520 is a wasteful number, since it uses less digits than its factorization.

805520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10082 (or 10076 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 805520 is about 897.5076601344. The cubic root of 805520 is about 93.0448005524.

The spelling of 805520 in words is "eight hundred five thousand, five hundred twenty".