815520 has 48 divisors (see below), whose sum is σ = 2570400. Its totient is φ = 217344.

The previous prime is 815519. The next prime is 815527. The reversal of 815520 is 25518.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (815527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 370 + ... + 1329.

It is an arithmetic number, because the mean of its divisors is an integer number (53550).

2⁸¹⁵⁵²⁰ is an apocalyptic number.

815520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

815520 is an abundant number, since it is smaller than the sum of its proper divisors (1754880).

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

815520 is a wasteful number, since it uses less digits than its factorization.

815520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1717 (or 1709 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 815520 is about 903.0614597025. The cubic root of 815520 is about 93.4282481155.

The spelling of 815520 in words is "eight hundred fifteen thousand, five hundred twenty".