166442541650509 has 8 divisors (see below), whose sum is σ = 166498373745792. Its totient is φ = 166386715065120.

The previous prime is 166442541650471. The next prime is 166442541650551. The reversal of 166442541650509 is 905056145244661.

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

It is a cyclic number.

It is not a de Polignac number, because 166442541650509 - 2³⁷ = 166305102697037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166442541650809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59499177 + ... + 62233729.

It is an arithmetic number, because the mean of its divisors is an integer number (20812296718224).

Almost surely, 2^{166442541650509} is an apocalyptic number.

It is an amenable number.

166442541650509 is a deficient number, since it is larger than the sum of its proper divisors (55832095283).

166442541650509 is a wasteful number, since it uses less digits than its factorization.

166442541650509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2754947.

The product of its (nonzero) digits is 31104000, while the sum is 58.

The spelling of 166442541650509 in words is "one hundred sixty-six trillion, four hundred forty-two billion, five hundred forty-one million, six hundred fifty thousand, five hundred nine".