166509977 has 8 divisors (see below), whose sum is σ = 178245600. Its totient is φ = 155071584.

The previous prime is 166509971. The next prime is 166509989. The reversal of 166509977 is 779905661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166509977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166509971) 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 7 ways as a sum of consecutive naturals, for example, 73148 + ... + 75389.

It is an arithmetic number, because the mean of its divisors is an integer number (22280700).

Almost surely, 2^166509977 is an apocalyptic number.

It is an amenable number.

166509977 is a deficient number, since it is larger than the sum of its proper divisors (11735623).

166509977 is a wasteful number, since it uses less digits than its factorization.

166509977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148615.

The product of its (nonzero) digits is 714420, while the sum is 50.

The square root of 166509977 is about 12903.8744956699. The cubic root of 166509977 is about 550.1486947824.

The spelling of 166509977 in words is "one hundred sixty-six million, five hundred nine thousand, nine hundred seventy-seven".