161181265728 has 112 divisors (see below), whose sum is σ = 513033182720. Its totient is φ = 43628004864.

The previous prime is 161181265717. The next prime is 161181265733. The reversal of 161181265728 is 827562181161.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3130426 + ... + 3181497.

Almost surely, 2^161181265728 is an apocalyptic number.

It is an amenable number.

161181265728 is an abundant number, since it is smaller than the sum of its proper divisors (351851916992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161181265728 is a wasteful number, since it uses less digits than its factorization.

161181265728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6311964 (or 6311954 counting only the distinct ones).

The product of its digits is 322560, while the sum is 48.

The spelling of 161181265728 in words is "one hundred sixty-one billion, one hundred eighty-one million, two hundred sixty-five thousand, seven hundred twenty-eight".