85311221 has 4 divisors (see below), whose sum is σ = 85788000. Its totient is φ = 84834444.

The previous prime is 85311179. The next prime is 85311223. The reversal of 85311221 is 12211358.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 85311221 - 2¹⁸ = 85049077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85311223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 238121 + ... + 238478.

It is an arithmetic number, because the mean of its divisors is an integer number (21447000).

Almost surely, 2^85311221 is an apocalyptic number.

It is an amenable number.

85311221 is a deficient number, since it is larger than the sum of its proper divisors (476779).

85311221 is a wasteful number, since it uses less digits than its factorization.

85311221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476778.

The product of its digits is 480, while the sum is 23.

The square root of 85311221 is about 9236.4073643381. The cubic root of 85311221 is about 440.2189354654.

Adding to 85311221 its reverse (12211358), we get a palindrome (97522579).

The spelling of 85311221 in words is "eighty-five million, three hundred eleven thousand, two hundred twenty-one".