161729568 has 576 divisors, whose sum is σ = 675682560. Its totient is φ = 36495360.

The previous prime is 161729563. The next prime is 161729593. The reversal of 161729568 is 865927161.

161729568 is a `hidden beast` number, since 1 + 61 + 7 + 29 + 568 = 666.

It is not an unprimeable number, because it can be changed into a prime (161729563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9513496 + ... + 9513512.

It is an arithmetic number, because the mean of its divisors is an integer number (1173060).

Almost surely, 2^161729568 is an apocalyptic number.

161729568 is a gapful number since it is divisible by the number (18) 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 161729568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (337841280).

161729568 is an abundant number, since it is smaller than the sum of its proper divisors (513952992).

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

161729568 is a wasteful number, since it uses less digits than its factorization.

161729568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78 (or 53 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 161729568 is about 12717.2940518021. The cubic root of 161729568 is about 544.8326709046.

The spelling of 161729568 in words is "one hundred sixty-one million, seven hundred twenty-nine thousand, five hundred sixty-eight".