166870213 has 2 divisors, whose sum is σ = 166870214. Its totient is φ = 166870212.

The previous prime is 166870211. The next prime is 166870219. The reversal of 166870213 is 312078661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159213924 + 7656289 = 12618^2 + 2767^2 .

It is a cyclic number.

It is not a de Polignac number, because 166870213 - 2¹ = 166870211 is a prime.

Together with 166870211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166870211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83435106 + 83435107.

It is an arithmetic number, because the mean of its divisors is an integer number (83435107).

Almost surely, 2^166870213 is an apocalyptic number.

It is an amenable number.

166870213 is a deficient number, since it is larger than the sum of its proper divisors (1).

166870213 is an equidigital number, since it uses as much as digits as its factorization.

166870213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 166870213 is about 12917.8253974885. The cubic root of 166870213 is about 550.5451487374.

The spelling of 166870213 in words is "one hundred sixty-six million, eight hundred seventy thousand, two hundred thirteen".