850478309 has 2 divisors, whose sum is σ = 850478310. Its totient is φ = 850478308.

The previous prime is 850478297. The next prime is 850478347. The reversal of 850478309 is 903874058.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 639938209 + 210540100 = 25297^2 + 14510^2 .

It is a cyclic number.

It is not a de Polignac number, because 850478309 - 2²⁰ = 849429733 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 850478309.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (850475309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425239154 + 425239155.

It is an arithmetic number, because the mean of its divisors is an integer number (425239155).

Almost surely, 2^850478309 is an apocalyptic number.

It is an amenable number.

850478309 is a deficient number, since it is larger than the sum of its proper divisors (1).

850478309 is an equidigital number, since it uses as much as digits as its factorization.

850478309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241920, while the sum is 44.

The square root of 850478309 is about 29162.9612522460. The cubic root of 850478309 is about 947.4458850147.

The spelling of 850478309 in words is "eight hundred fifty million, four hundred seventy-eight thousand, three hundred nine".