85840709 has 2 divisors, whose sum is σ = 85840710. Its totient is φ = 85840708.

The previous prime is 85840687. The next prime is 85840717. The reversal of 85840709 is 90704858.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85840225 + 484 = 9265^2 + 22^2 .

It is a cyclic number.

It is not a de Polignac number, because 85840709 - 2⁸ = 85840453 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85840739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42920354 + 42920355.

It is an arithmetic number, because the mean of its divisors is an integer number (42920355).

Almost surely, 2^85840709 is an apocalyptic number.

It is an amenable number.

85840709 is a deficient number, since it is larger than the sum of its proper divisors (1).

85840709 is an equidigital number, since it uses as much as digits as its factorization.

85840709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 85840709 is about 9265.0261197689. The cubic root of 85840709 is about 441.1278040669.

The spelling of 85840709 in words is "eighty-five million, eight hundred forty thousand, seven hundred nine".