161545 has 4 divisors (see below), whose sum is σ = 193860. Its totient is φ = 129232.

The previous prime is 161543. The next prime is 161561. The reversal of 161545 is 545161.

161545 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 109561 + 51984 = 331^2 + 228^2 .

It is a cyclic number.

It is not a de Polignac number, because 161545 - 2¹ = 161543 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

161545 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (161543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16150 + ... + 16159.

It is an arithmetic number, because the mean of its divisors is an integer number (48465).

2¹⁶¹⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

161545 is a deficient number, since it is larger than the sum of its proper divisors (32315).

161545 is an equidigital number, since it uses as much as digits as its factorization.

161545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32314.

The product of its digits is 600, while the sum is 22.

The square root of 161545 is about 401.9266102163. The cubic root of 161545 is about 54.4625335176.

The spelling of 161545 in words is "one hundred sixty-one thousand, five hundred forty-five".