166721716705 has 8 divisors (see below), whose sum is σ = 210595852800. Its totient is φ = 126357511536.

The previous prime is 166721716661. The next prime is 166721716801. The reversal of 166721716705 is 507617127661.

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

It is not a de Polignac number, because 166721716705 - 2²⁹ = 166184845793 is a prime.

It is a super-2 number, since 2×166721716705² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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, 877482625 + ... + 877482814.

It is an arithmetic number, because the mean of its divisors is an integer number (26324481600).

Almost surely, 2^166721716705 is an apocalyptic number.

It is an amenable number.

166721716705 is a deficient number, since it is larger than the sum of its proper divisors (43874136095).

166721716705 is a wasteful number, since it uses less digits than its factorization.

166721716705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1754965463.

The product of its (nonzero) digits is 740880, while the sum is 49.

The spelling of 166721716705 in words is "one hundred sixty-six billion, seven hundred twenty-one million, seven hundred sixteen thousand, seven hundred five".