1666650009 has 16 divisors (see below), whose sum is σ = 2234568960. Its totient is φ = 1104929280.

The previous prime is 1666650001. The next prime is 1666650047. The reversal of 1666650009 is 9000566661.

It is not a de Polignac number, because 1666650009 - 2³ = 1666650001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1666650001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 799849 + ... + 801929.

It is an arithmetic number, because the mean of its divisors is an integer number (139660560).

Almost surely, 2^1666650009 is an apocalyptic number.

It is an amenable number.

1666650009 is a deficient number, since it is larger than the sum of its proper divisors (567918951).

1666650009 is a wasteful number, since it uses less digits than its factorization.

1666650009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3440.

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 1666650009 is about 40824.6250319583. The cubic root of 1666650009 is about 1185.6271515140.

The spelling of 1666650009 in words is "one billion, six hundred sixty-six million, six hundred fifty thousand, nine".