166201993 has 2 divisors, whose sum is σ = 166201994. Its totient is φ = 166201992.

The previous prime is 166201963. The next prime is 166201999. The reversal of 166201993 is 399102661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 146603664 + 19598329 = 12108^2 + 4427^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166201993 is a prime.

It is not a weakly prime, because it can be changed into another prime (166201999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83100996 + 83100997.

It is an arithmetic number, because the mean of its divisors is an integer number (83100997).

Almost surely, 2^166201993 is an apocalyptic number.

It is an amenable number.

166201993 is a deficient number, since it is larger than the sum of its proper divisors (1).

166201993 is an equidigital number, since it uses as much as digits as its factorization.

166201993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 166201993 is about 12891.9351922045. The cubic root of 166201993 is about 549.8092925593.

The spelling of 166201993 in words is "one hundred sixty-six million, two hundred one thousand, nine hundred ninety-three".