161243645875 has 32 divisors (see below), whose sum is σ = 222568609536. Its totient is φ = 115854019200.

The previous prime is 161243645869. The next prime is 161243645879. The reversal of 161243645875 is 578546342161.

It is not a de Polignac number, because 161243645875 - 2⁹ = 161243645363 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161243645879) 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, 1280779 + ... + 1401028.

It is an arithmetic number, because the mean of its divisors is an integer number (6955269048).

Almost surely, 2^161243645875 is an apocalyptic number.

161243645875 is a deficient number, since it is larger than the sum of its proper divisors (61324963661).

161243645875 is a wasteful number, since it uses less digits than its factorization.

161243645875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2681872 (or 2681862 counting only the distinct ones).

The product of its digits is 4838400, while the sum is 52.

The spelling of 161243645875 in words is "one hundred sixty-one billion, two hundred forty-three million, six hundred forty-five thousand, eight hundred seventy-five".