166163644440 has 96 divisors (see below), whose sum is σ = 563511517920. Its totient is φ = 42383768064.

The previous prime is 166163644397. The next prime is 166163644441. The reversal of 166163644440 is 44446361661.

It is a happy number.

166163644440 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 636 + 4 + 4 + 4 + 4 + 0 = 666.

It is a super-2 number, since 2×166163644440² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166163644441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10025757 + ... + 10042316.

It is an arithmetic number, because the mean of its divisors is an integer number (5869911645).

Almost surely, 2^166163644440 is an apocalyptic number.

166163644440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166163644440 is an abundant number, since it is smaller than the sum of its proper divisors (397347873480).

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

166163644440 is a wasteful number, since it uses less digits than its factorization.

166163644440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20068113 (or 20068106 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 45.

The spelling of 166163644440 in words is "one hundred sixty-six billion, one hundred sixty-three million, six hundred forty-four thousand, four hundred forty".