166605501601 has 8 divisors (see below), whose sum is σ = 207715950144. Its totient is φ = 129822468720.

The previous prime is 166605501581. The next prime is 166605501617. The reversal of 166605501601 is 106105506661.

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

It is not a de Polignac number, because 166605501601 - 2¹⁹ = 166604977313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166605511601) 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, 1081853830 + ... + 1081853983.

It is an arithmetic number, because the mean of its divisors is an integer number (25964493768).

Almost surely, 2^166605501601 is an apocalyptic number.

166605501601 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

166605501601 is a deficient number, since it is larger than the sum of its proper divisors (41110448543).

166605501601 is a wasteful number, since it uses less digits than its factorization.

166605501601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2163707831.

The product of its (nonzero) digits is 32400, while the sum is 37.

The spelling of 166605501601 in words is "one hundred sixty-six billion, six hundred five million, five hundred one thousand, six hundred one".