163581979680 has 768 divisors, whose sum is σ = 683840102400. Its totient is φ = 35730616320.

The previous prime is 163581979669. The next prime is 163581979699. The reversal of 163581979680 is 86979185361.

163581979680 is a `hidden beast` number, since 1 + 6 + 358 + 197 + 96 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

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 127 ways as a sum of consecutive naturals, for example, 90325975 + ... + 90327785.

It is an arithmetic number, because the mean of its divisors is an integer number (890416800).

Almost surely, 2^163581979680 is an apocalyptic number.

163581979680 is a gapful number since it is divisible by the number (10) 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 163581979680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (341920051200).

163581979680 is an abundant number, since it is smaller than the sum of its proper divisors (520258122720).

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

163581979680 is a wasteful number, since it uses less digits than its factorization.

163581979680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1974 (or 1960 counting only the distinct ones).

The product of its (nonzero) digits is 19595520, while the sum is 63.

The spelling of 163581979680 in words is "one hundred sixty-three billion, five hundred eighty-one million, nine hundred seventy-nine thousand, six hundred eighty".