66150209 has 2 divisors, whose sum is σ = 66150210. Its totient is φ = 66150208.

The previous prime is 66150173. The next prime is 66150283. The reversal of 66150209 is 90205166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53333809 + 12816400 = 7303^2 + 3580^2 .

It is a cyclic number.

It is not a de Polignac number, because 66150209 - 2²⁰ = 65101633 is a prime.

It is not a weakly prime, because it can be changed into another prime (66150299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33075104 + 33075105.

It is an arithmetic number, because the mean of its divisors is an integer number (33075105).

Almost surely, 2^66150209 is an apocalyptic number.

It is an amenable number.

66150209 is a deficient number, since it is larger than the sum of its proper divisors (1).

66150209 is an equidigital number, since it uses as much as digits as its factorization.

66150209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 66150209 is about 8133.2778754940. The cubic root of 66150209 is about 404.4303508962.

The spelling of 66150209 in words is "sixty-six million, one hundred fifty thousand, two hundred nine".