161901945695168 has 56 divisors (see below), whose sum is σ = 367173709948800. Its totient is φ = 69385938524928.

The previous prime is 161901945695159. The next prime is 161901945695179. The reversal of 161901945695168 is 861596549109161.

It is a tau number, because it is divible by the number of its divisors (56).

It is a super-2 number, since 2×161901945695168² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51433643 + ... + 54490581.

Almost surely, 2^{161901945695168} is an apocalyptic number.

It is an amenable number.

161901945695168 is an abundant number, since it is smaller than the sum of its proper divisors (205271764253632).

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

161901945695168 is a wasteful number, since it uses less digits than its factorization.

161901945695168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3175177 (or 3175167 counting only the distinct ones).

The product of its (nonzero) digits is 125971200, while the sum is 71.

The spelling of 161901945695168 in words is "one hundred sixty-one trillion, nine hundred one billion, nine hundred forty-five million, six hundred ninety-five thousand, one hundred sixty-eight".