166636663 has 2 divisors, whose sum is σ = 166636664. Its totient is φ = 166636662.

The previous prime is 166636661. The next prime is 166636699. The reversal of 166636663 is 366636661.

It is a weak prime.

It is an emirp because it is prime and its reverse (366636661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166636663 - 2¹ = 166636661 is a prime.

Together with 166636661, 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 (166636661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83318331 + 83318332.

It is an arithmetic number, because the mean of its divisors is an integer number (83318332).

Almost surely, 2^166636663 is an apocalyptic number.

166636663 is a deficient number, since it is larger than the sum of its proper divisors (1).

166636663 is an equidigital number, since it uses as much as digits as its factorization.

166636663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 419904, while the sum is 43.

The square root of 166636663 is about 12908.7823980420. The cubic root of 166636663 is about 550.2881828591.

The spelling of 166636663 in words is "one hundred sixty-six million, six hundred thirty-six thousand, six hundred sixty-three".