85481521 has 2 divisors, whose sum is σ = 85481522. Its totient is φ = 85481520.

The previous prime is 85481519. The next prime is 85481567. The reversal of 85481521 is 12518458.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46730896 + 38750625 = 6836^2 + 6225^2 .

It is a cyclic number.

It is not a de Polignac number, because 85481521 - 2¹ = 85481519 is a prime.

Together with 85481519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (85481621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42740760 + 42740761.

It is an arithmetic number, because the mean of its divisors is an integer number (42740761).

Almost surely, 2^85481521 is an apocalyptic number.

It is an amenable number.

85481521 is a deficient number, since it is larger than the sum of its proper divisors (1).

85481521 is an equidigital number, since it uses as much as digits as its factorization.

85481521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12800, while the sum is 34.

The square root of 85481521 is about 9245.6217205767. The cubic root of 85481521 is about 440.5116654408.

Adding to 85481521 its reverse (12518458), we get a palindrome (97999979).

The spelling of 85481521 in words is "eighty-five million, four hundred eighty-one thousand, five hundred twenty-one".