85215331 has 4 divisors (see below), whose sum is σ = 85237600. Its totient is φ = 85193064.

The previous prime is 85215313. The next prime is 85215337. The reversal of 85215331 is 13351258.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 85215331 - 2¹¹ = 85213283 is a prime.

It is a super-2 number, since 2×85215331² = 14523305274879122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 85215331.

It is not an unprimeable number, because it can be changed into a prime (85215337) 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, 3771 + ... + 13588.

It is an arithmetic number, because the mean of its divisors is an integer number (21309400).

Almost surely, 2^85215331 is an apocalyptic number.

85215331 is a deficient number, since it is larger than the sum of its proper divisors (22269).

85215331 is a wasteful number, since it uses less digits than its factorization.

85215331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22268.

The product of its digits is 3600, while the sum is 28.

The square root of 85215331 is about 9231.2150337862. The cubic root of 85215331 is about 440.0539379469.

Adding to 85215331 its reverse (13351258), we get a palindrome (98566589).

The spelling of 85215331 in words is "eighty-five million, two hundred fifteen thousand, three hundred thirty-one".