161905557076 has 12 divisors (see below), whose sum is σ = 293104888020. Its totient is φ = 78161303360.

The previous prime is 161905557031. The next prime is 161905557091. The reversal of 161905557076 is 670755509161.

161905557076 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 83099592900 + 78805964176 = 288270^2 + 280724^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 697868665 + ... + 697868896.

It is an arithmetic number, because the mean of its divisors is an integer number (24425407335).

Almost surely, 2^161905557076 is an apocalyptic number.

It is an amenable number.

161905557076 is a deficient number, since it is larger than the sum of its proper divisors (131199330944).

161905557076 is a wasteful number, since it uses less digits than its factorization.

161905557076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1395737594 (or 1395737592 counting only the distinct ones).

The product of its (nonzero) digits is 1984500, while the sum is 52.

The spelling of 161905557076 in words is "one hundred sixty-one billion, nine hundred five million, five hundred fifty-seven thousand, seventy-six".