166163644391 has 8 divisors (see below), whose sum is σ = 181613395584. Its totient is φ = 151344495360.

The previous prime is 166163644379. The next prime is 166163644397. The reversal of 166163644391 is 193446361661.

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 166163644391 - 2¹⁸ = 166163382247 is a prime.

It is a super-2 number, since 2×166163644391² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166163644397) 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, 157649990 + ... + 157651043.

It is an arithmetic number, because the mean of its divisors is an integer number (22701674448).

Almost surely, 2^166163644391 is an apocalyptic number.

166163644391 is a deficient number, since it is larger than the sum of its proper divisors (15449751193).

166163644391 is a wasteful number, since it uses less digits than its factorization.

166163644391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315301081.

The product of its digits is 1679616, while the sum is 50.

The spelling of 166163644391 in words is "one hundred sixty-six billion, one hundred sixty-three million, six hundred forty-four thousand, three hundred ninety-one".