85117821 has 8 divisors (see below), whose sum is σ = 113729280. Its totient is φ = 56625792.

The previous prime is 85117819. The next prime is 85117843. The reversal of 85117821 is 12871158.

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

It is not a de Polignac number, because 85117821 - 2¹ = 85117819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85117801) 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, 28180 + ... + 31053.

It is an arithmetic number, because the mean of its divisors is an integer number (14216160).

Almost surely, 2^85117821 is an apocalyptic number.

It is an amenable number.

85117821 is a deficient number, since it is larger than the sum of its proper divisors (28611459).

85117821 is a wasteful number, since it uses less digits than its factorization.

85117821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59715.

The product of its digits is 4480, while the sum is 33.

The square root of 85117821 is about 9225.9319854419. The cubic root of 85117821 is about 439.8860259204.

Adding to 85117821 its reverse (12871158), we get a palindrome (97988979).

The spelling of 85117821 in words is "eighty-five million, one hundred seventeen thousand, eight hundred twenty-one".