161728432305 has 32 divisors (see below), whose sum is σ = 283866716160. Its totient is φ = 77975705280.

The previous prime is 161728432301. The next prime is 161728432373. The reversal of 161728432305 is 503234827161.

It is not a de Polignac number, because 161728432305 - 2² = 161728432301 is a prime.

It is a super-2 number, since 2×161728432305² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161728432301) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2708377 + ... + 2767446.

It is an arithmetic number, because the mean of its divisors is an integer number (8870834880).

Almost surely, 2^161728432305 is an apocalyptic number.

161728432305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161728432305 is a deficient number, since it is larger than the sum of its proper divisors (122138283855).

161728432305 is a wasteful number, since it uses less digits than its factorization.

161728432305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5476021.

The product of its (nonzero) digits is 241920, while the sum is 42.

The spelling of 161728432305 in words is "one hundred sixty-one billion, seven hundred twenty-eight million, four hundred thirty-two thousand, three hundred five".