85590809 has 2 divisors, whose sum is σ = 85590810. Its totient is φ = 85590808.

The previous prime is 85590781. The next prime is 85590823. The reversal of 85590809 is 90809558.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71453209 + 14137600 = 8453^2 + 3760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85590809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85590809.

It is not a weakly prime, because it can be changed into another prime (85590859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42795404 + 42795405.

It is an arithmetic number, because the mean of its divisors is an integer number (42795405).

Almost surely, 2^85590809 is an apocalyptic number.

It is an amenable number.

85590809 is a deficient number, since it is larger than the sum of its proper divisors (1).

85590809 is an equidigital number, since it uses as much as digits as its factorization.

85590809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129600, while the sum is 44.

The square root of 85590809 is about 9251.5300896662. The cubic root of 85590809 is about 440.6993166670.

The spelling of 85590809 in words is "eighty-five million, five hundred ninety thousand, eight hundred nine".