166671887 has 2 divisors, whose sum is σ = 166671888. Its totient is φ = 166671886.

The previous prime is 166671839. The next prime is 166671889. The reversal of 166671887 is 788176661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166671887 is a prime.

It is a super-2 number, since 2×166671887² = 55559035832281538, which contains 22 as substring.

Together with 166671889, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166671889) 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, 83335943 + 83335944.

It is an arithmetic number, because the mean of its divisors is an integer number (83335944).

Almost surely, 2^166671887 is an apocalyptic number.

166671887 is a deficient number, since it is larger than the sum of its proper divisors (1).

166671887 is an equidigital number, since it uses as much as digits as its factorization.

166671887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 677376, while the sum is 50.

The square root of 166671887 is about 12910.1466684155. The cubic root of 166671887 is about 550.3269538094.

The spelling of 166671887 in words is "one hundred sixty-six million, six hundred seventy-one thousand, eight hundred eighty-seven".