161004505 has 16 divisors (see below), whose sum is σ = 196401024. Its totient is φ = 126691200.

The previous prime is 161004497. The next prime is 161004509. The reversal of 161004505 is 505400161.

It is not a de Polignac number, because 161004505 - 2³ = 161004497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161004509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79789 + ... + 81781.

It is an arithmetic number, because the mean of its divisors is an integer number (12275064).

Almost surely, 2^161004505 is an apocalyptic number.

It is an amenable number.

161004505 is a deficient number, since it is larger than the sum of its proper divisors (35396519).

161004505 is a wasteful number, since it uses less digits than its factorization.

161004505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256.

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

The square root of 161004505 is about 12688.7550610767. The cubic root of 161004505 is about 544.0172565622.

Adding to 161004505 its reverse (505400161), we get a palindrome (666404666).

The spelling of 161004505 in words is "one hundred sixty-one million, four thousand, five hundred five".