85861609 has 2 divisors, whose sum is σ = 85861610. Its totient is φ = 85861608.

The previous prime is 85861549. The next prime is 85861613. The reversal of 85861609 is 90616858.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84695209 + 1166400 = 9203^2 + 1080^2 .

It is a cyclic number.

It is not a de Polignac number, because 85861609 - 2⁷ = 85861481 is a prime.

It is not a weakly prime, because it can be changed into another prime (85861619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42930804 + 42930805.

It is an arithmetic number, because the mean of its divisors is an integer number (42930805).

Almost surely, 2^85861609 is an apocalyptic number.

It is an amenable number.

85861609 is a deficient number, since it is larger than the sum of its proper divisors (1).

85861609 is an equidigital number, since it uses as much as digits as its factorization.

85861609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 85861609 is about 9266.1539486456. The cubic root of 85861609 is about 441.1636022450.

The spelling of 85861609 in words is "eighty-five million, eight hundred sixty-one thousand, six hundred nine".