85478609 has 2 divisors, whose sum is σ = 85478610. Its totient is φ = 85478608.

The previous prime is 85478531. The next prime is 85478611. The reversal of 85478609 is 90687458.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47224384 + 38254225 = 6872^2 + 6185^2 .

It is a cyclic number.

It is not a de Polignac number, because 85478609 - 2²⁴ = 68701393 is a prime.

Together with 85478611, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85478699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42739304 + 42739305.

It is an arithmetic number, because the mean of its divisors is an integer number (42739305).

Almost surely, 2^85478609 is an apocalyptic number.

It is an amenable number.

85478609 is a deficient number, since it is larger than the sum of its proper divisors (1).

85478609 is an equidigital number, since it uses as much as digits as its factorization.

85478609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 483840, while the sum is 47.

The square root of 85478609 is about 9245.4642392905. The cubic root of 85478609 is about 440.5066632504.

The spelling of 85478609 in words is "eighty-five million, four hundred seventy-eight thousand, six hundred nine".