161728432489 has 8 divisors (see below), whose sum is σ = 174797854280. Its totient is φ = 148748835456.

The previous prime is 161728432487. The next prime is 161728432493. The reversal of 161728432489 is 984234827161.

It can be written as a sum of positive squares in 4 ways, for example, as 70560000 + 161657872489 = 8400^2 + 402067^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161728432489 - 2¹ = 161728432487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161728432487) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 22452444 + ... + 22459645.

It is an arithmetic number, because the mean of its divisors is an integer number (21849731785).

Almost surely, 2^161728432489 is an apocalyptic number.

It is an amenable number.

161728432489 is a deficient number, since it is larger than the sum of its proper divisors (13069421791).

161728432489 is a wasteful number, since it uses less digits than its factorization.

161728432489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44912379.

The product of its digits is 4644864, while the sum is 55.

The spelling of 161728432489 in words is "one hundred sixty-one billion, seven hundred twenty-eight million, four hundred thirty-two thousand, four hundred eighty-nine".