166647649 has 16 divisors (see below), whose sum is σ = 194802048. Its totient is φ = 139617792.

The previous prime is 166647647. The next prime is 166647671. The reversal of 166647649 is 946746661.

It is a cyclic number.

It is not a de Polignac number, because 166647649 - 2¹ = 166647647 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166647641) 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, 54879 + ... + 57835.

It is an arithmetic number, because the mean of its divisors is an integer number (12175128).

Almost surely, 2^166647649 is an apocalyptic number.

It is an amenable number.

166647649 is a deficient number, since it is larger than the sum of its proper divisors (28154399).

166647649 is an equidigital number, since it uses as much as digits as its factorization.

166647649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3144.

The product of its digits is 1306368, while the sum is 49.

The square root of 166647649 is about 12909.2079152828. The cubic root of 166647649 is about 550.3002757023.

The spelling of 166647649 in words is "one hundred sixty-six million, six hundred forty-seven thousand, six hundred forty-nine".