161880320 has 216 divisors, whose sum is σ = 471857400. Its totient is φ = 52985856.

The previous prime is 161880319. The next prime is 161880343. The reversal of 161880320 is 23088161.

It can be written as a sum of positive squares in 4 ways, for example, as 4528384 + 157351936 = 2128^2 + 12544^2 .

It is a Harshad number since it is a multiple of its sum of digits (29).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1818836 + ... + 1818924.

It is an arithmetic number, because the mean of its divisors is an integer number (2184525).

Almost surely, 2^161880320 is an apocalyptic number.

161880320 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 161880320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235928700).

161880320 is an abundant number, since it is smaller than the sum of its proper divisors (309977080).

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

161880320 is an equidigital number, since it uses as much as digits as its factorization.

161880320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 161880320 is about 12723.2197182946. The cubic root of 161880320 is about 545.0019021901.

The spelling of 161880320 in words is "one hundred sixty-one million, eight hundred eighty thousand, three hundred twenty".