166957709 has 2 divisors, whose sum is σ = 166957710. Its totient is φ = 166957708.

The previous prime is 166957657. The next prime is 166957733. The reversal of 166957709 is 907759661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139948900 + 27008809 = 11830^2 + 5197^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166957709 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166957309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83478854 + 83478855.

It is an arithmetic number, because the mean of its divisors is an integer number (83478855).

Almost surely, 2^166957709 is an apocalyptic number.

It is an amenable number.

166957709 is a deficient number, since it is larger than the sum of its proper divisors (1).

166957709 is an equidigital number, since it uses as much as digits as its factorization.

166957709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 714420, while the sum is 50.

The square root of 166957709 is about 12921.2115917974. The cubic root of 166957709 is about 550.6413554056.

The spelling of 166957709 in words is "one hundred sixty-six million, nine hundred fifty-seven thousand, seven hundred nine".