166905647 has 2 divisors, whose sum is σ = 166905648. Its totient is φ = 166905646.

The previous prime is 166905637. The next prime is 166905649. The reversal of 166905647 is 746509661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166905647 - 2⁸ = 166905391 is a prime.

Together with 166905649, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 166905598 and 166905607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166905649) 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 as a sum of consecutive naturals, namely, 83452823 + 83452824.

It is an arithmetic number, because the mean of its divisors is an integer number (83452824).

Almost surely, 2^166905647 is an apocalyptic number.

166905647 is a deficient number, since it is larger than the sum of its proper divisors (1).

166905647 is an equidigital number, since it uses as much as digits as its factorization.

166905647 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 44.

The square root of 166905647 is about 12919.1968403612. The cubic root of 166905647 is about 550.5841144218.

The spelling of 166905647 in words is "one hundred sixty-six million, nine hundred five thousand, six hundred forty-seven".