85216321 has 2 divisors, whose sum is σ = 85216322. Its totient is φ = 85216320.

The previous prime is 85216301. The next prime is 85216361. The reversal of 85216321 is 12361258.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47761921 + 37454400 = 6911^2 + 6120^2 .

It is a cyclic number.

It is not a de Polignac number, because 85216321 - 2¹¹ = 85214273 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 85216321.

It is not a weakly prime, because it can be changed into another prime (85216301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42608160 + 42608161.

It is an arithmetic number, because the mean of its divisors is an integer number (42608161).

Almost surely, 2^85216321 is an apocalyptic number.

It is an amenable number.

85216321 is a deficient number, since it is larger than the sum of its proper divisors (1).

85216321 is an equidigital number, since it uses as much as digits as its factorization.

85216321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 28.

The square root of 85216321 is about 9231.2686560407. The cubic root of 85216321 is about 440.0556420679.

Adding to 85216321 its reverse (12361258), we get a palindrome (97577579).

The spelling of 85216321 in words is "eighty-five million, two hundred sixteen thousand, three hundred twenty-one".