85521 has 8 divisors (see below), whose sum is σ = 118080. Its totient is φ = 54992.

The previous prime is 85517. The next prime is 85523. The reversal of 85521 is 12558.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 85521 - 2² = 85517 is a prime.

It is a Curzon number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (85523) 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 7 ways as a sum of consecutive naturals, for example, 405 + ... + 578.

It is an arithmetic number, because the mean of its divisors is an integer number (14760).

2⁸⁵⁵²¹ is an apocalyptic number.

It is an amenable number.

85521 is a deficient number, since it is larger than the sum of its proper divisors (32559).

85521 is a wasteful number, since it uses less digits than its factorization.

85521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015.

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

The square root of 85521 is about 292.4397373819. The cubic root of 85521 is about 44.0579470674.

It can be divided in two parts, 855 and 21, that multiplied together give a triangular number (17955 = T₁₈₉).

The spelling of 85521 in words is "eighty-five thousand, five hundred twenty-one".