818520 has 64 divisors (see below), whose sum is σ = 2592000. Its totient is φ = 206208.

The previous prime is 818509. The next prime is 818561. The reversal of 818520 is 25818.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

818520 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2101 + ... + 2459.

It is an arithmetic number, because the mean of its divisors is an integer number (40500).

2⁸¹⁸⁵²⁰ 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 818520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1296000).

818520 is an abundant number, since it is smaller than the sum of its proper divisors (1773480).

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

818520 is a wasteful number, since it uses less digits than its factorization.

818520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 24.

The square root of 818520 is about 904.7209514541. The cubic root of 818520 is about 93.5426707156.

It can be divided in two parts, 8 and 18520, that added together give a triangular number (18528 = T₁₉₂).

The spelling of 818520 in words is "eight hundred eighteen thousand, five hundred twenty".