85520 has 20 divisors (see below), whose sum is σ = 199020. Its totient is φ = 34176.

The previous prime is 85517. The next prime is 85523. The reversal of 85520 is 2558.

It is an interprime number because it is at equal distance from previous prime (85517) and next prime (85523).

It can be written as a sum of positive squares in 2 ways, for example, as 35344 + 50176 = 188^2 + 224^2 .

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 nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 85492 and 85501.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 85520.

It is not an unprimeable number, because it can be changed into a prime (85523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 455 + ... + 614.

It is an arithmetic number, because the mean of its divisors is an integer number (9951).

2⁸⁵⁵²⁰ is an apocalyptic number.

85520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

85520 is an abundant number, since it is smaller than the sum of its proper divisors (113500).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99510).

85520 is a wasteful number, since it uses less digits than its factorization.

85520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1082 (or 1076 counting only the distinct ones).

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

The square root of 85520 is about 292.4380276229. The cubic root of 85520 is about 44.0577753430.

The spelling of 85520 in words is "eighty-five thousand, five hundred twenty".