161909138866176 has 1440 divisors, whose sum is σ = 553424576560128. Its totient is φ = 45137673584640.

The previous prime is 161909138866141. The next prime is 161909138866213. The reversal of 161909138866176 is 671668831909161.

It is a happy number.

161909138866176 is a `hidden beast` number, since 1 + 6 + 1 + 90 + 91 + 388 + 6 + 6 + 1 + 76 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 295994769135 + ... + 295994769681.

Almost surely, 2^{161909138866176} is an apocalyptic number.

161909138866176 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161909138866176, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276712288280064).

161909138866176 is an abundant number, since it is smaller than the sum of its proper divisors (391515437693952).

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

161909138866176 is a wasteful number, since it uses less digits than its factorization.

161909138866176 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935 (or 906 counting only the distinct ones).

The product of its (nonzero) digits is 141087744, while the sum is 72.

The spelling of 161909138866176 in words is "one hundred sixty-one trillion, nine hundred nine billion, one hundred thirty-eight million, eight hundred sixty-six thousand, one hundred seventy-six".