8478209 has 2 divisors, whose sum is σ = 8478210. Its totient is φ = 8478208.

The previous prime is 8478187. The next prime is 8478259. The reversal of 8478209 is 9028748.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8151025 + 327184 = 2855^2 + 572^2 .

It is a cyclic number.

It is not a de Polignac number, because 8478209 - 2¹⁶ = 8412673 is a prime.

It is not a weakly prime, because it can be changed into another prime (8478259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4239104 + 4239105.

It is an arithmetic number, because the mean of its divisors is an integer number (4239105).

Almost surely, 2^8478209 is an apocalyptic number.

It is an amenable number.

8478209 is a deficient number, since it is larger than the sum of its proper divisors (1).

8478209 is an equidigital number, since it uses as much as digits as its factorization.

8478209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 8478209 is about 2911.7364235109. The cubic root of 8478209 is about 203.9082071327.

The spelling of 8478209 in words is "eight million, four hundred seventy-eight thousand, two hundred nine".