165931217436672 has 720 divisors, whose sum is σ = 525575315026944. Its totient is φ = 50217615360000.

The previous prime is 165931217436661. The next prime is 165931217436679. The reversal of 165931217436672 is 276634712139561.

165931217436672 is a `hidden beast` number, since 1 + 6 + 5 + 9 + 3 + 121 + 7 + 436 + 6 + 72 = 666.

It is a super-2 number, since 2×165931217436672² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165931217436679) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25721779047 + ... + 25721785497.

Almost surely, 2^{165931217436672} is an apocalyptic number.

165931217436672 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165931217436672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262787657513472).

165931217436672 is an abundant number, since it is smaller than the sum of its proper divisors (359644097590272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165931217436672 is a wasteful number, since it uses less digits than its factorization.

165931217436672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6864 (or 6835 counting only the distinct ones).

The product of its digits is 68584320, while the sum is 63.

The spelling of 165931217436672 in words is "one hundred sixty-five trillion, nine hundred thirty-one billion, two hundred seventeen million, four hundred thirty-six thousand, six hundred seventy-two".