664087166 has 4 divisors (see below), whose sum is σ = 996130752. Its totient is φ = 332043582.

The previous prime is 664087163. The next prime is 664087169. The reversal of 664087166 is 661780466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 661780466 = 2 ⋅330890233.

It is an interprime number because it is at equal distance from previous prime (664087163) and next prime (664087169).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664087163) 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, 166021790 + ... + 166021793.

It is an arithmetic number, because the mean of its divisors is an integer number (249032688).

Almost surely, 2^664087166 is an apocalyptic number.

664087166 is a deficient number, since it is larger than the sum of its proper divisors (332043586).

664087166 is a wasteful number, since it uses less digits than its factorization.

664087166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332043585.

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 664087166 is about 25769.8887463644. Note that the first 3 decimals coincide. The cubic root of 664087166 is about 872.4523077463.

The spelling of 664087166 in words is "six hundred sixty-four million, eighty-seven thousand, one hundred sixty-six".