161181265729 has 8 divisors (see below), whose sum is σ = 175859066880. Its totient is φ = 146507624400.

The previous prime is 161181265717. The next prime is 161181265733. The reversal of 161181265729 is 927562181161.

161181265729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 161181265729 - 2⁵ = 161181265697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161181265789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 958657 + ... + 1114174.

It is an arithmetic number, because the mean of its divisors is an integer number (21982383360).

Almost surely, 2^161181265729 is an apocalyptic number.

It is an amenable number.

161181265729 is a deficient number, since it is larger than the sum of its proper divisors (14677801151).

161181265729 is a wasteful number, since it uses less digits than its factorization.

161181265729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2079911.

The product of its digits is 362880, while the sum is 49.

The spelling of 161181265729 in words is "one hundred sixty-one billion, one hundred eighty-one million, two hundred sixty-five thousand, seven hundred twenty-nine".