166663913 has 6 divisors (see below), whose sum is σ = 180470574. Its totient is φ = 153843456.

The previous prime is 166663883. The next prime is 166663933. The reversal of 166663913 is 319366661.

It can be written as a sum of positive squares in 3 ways, for example, as 17530969 + 149132944 = 4187^2 + 12212^2 .

It is not a de Polignac number, because 166663913 - 2²⁰ = 165615337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166663933) 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 in 5 ways as a sum of consecutive naturals, for example, 492920 + ... + 493257.

It is an arithmetic number, because the mean of its divisors is an integer number (30078429).

Almost surely, 2^166663913 is an apocalyptic number.

166663913 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

166663913 is a deficient number, since it is larger than the sum of its proper divisors (13806661).

166663913 is an equidigital number, since it uses as much as digits as its factorization.

166663913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986203 (or 986190 counting only the distinct ones).

The product of its digits is 104976, while the sum is 41.

The square root of 166663913 is about 12909.8378378661. The cubic root of 166663913 is about 550.3181773301.

The spelling of 166663913 in words is "one hundred sixty-six million, six hundred sixty-three thousand, nine hundred thirteen".