84065209 has 2 divisors, whose sum is σ = 84065210. Its totient is φ = 84065208.

The previous prime is 84065197. The next prime is 84065263. The reversal of 84065209 is 90256048.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73359225 + 10705984 = 8565^2 + 3272^2 .

It is a cyclic number.

It is not a de Polignac number, because 84065209 - 2⁷ = 84065081 is a prime.

It is not a weakly prime, because it can be changed into another prime (84065309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42032604 + 42032605.

It is an arithmetic number, because the mean of its divisors is an integer number (42032605).

Almost surely, 2^84065209 is an apocalyptic number.

It is an amenable number.

84065209 is a deficient number, since it is larger than the sum of its proper divisors (1).

84065209 is an equidigital number, since it uses as much as digits as its factorization.

84065209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 84065209 is about 9168.7081423721. The cubic root of 84065209 is about 438.0652116856.

It can be divided in two parts, 840 and 65209, that added together give a square (66049 = 257²).

The spelling of 84065209 in words is "eighty-four million, sixty-five thousand, two hundred nine".