166666481 has 2 divisors, whose sum is σ = 166666482. Its totient is φ = 166666480.

The previous prime is 166666469. The next prime is 166666547. The reversal of 166666481 is 184666661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97693456 + 68973025 = 9884^2 + 8305^2 .

It is an emirp because it is prime and its reverse (184666661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166666481 - 2⁶ = 166666417 is a prime.

It is a super-2 number, since 2×166666481² = 55555431777846722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (165666481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83333240 + 83333241.

It is an arithmetic number, because the mean of its divisors is an integer number (83333241).

Almost surely, 2^166666481 is an apocalyptic number.

It is an amenable number.

166666481 is a deficient number, since it is larger than the sum of its proper divisors (1).

166666481 is an equidigital number, since it uses as much as digits as its factorization.

166666481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 44.

The square root of 166666481 is about 12909.9372965170. The cubic root of 166666481 is about 550.3210037964.

The spelling of 166666481 in words is "one hundred sixty-six million, six hundred sixty-six thousand, four hundred eighty-one".