161161606566 has 12 divisors (see below), whose sum is σ = 349183480932. Its totient is φ = 53720535516.

The previous prime is 161161606559. The next prime is 161161606603. The reversal of 161161606566 is 665606161161.

161161606566 is a `hidden beast` number, since 1 + 61 + 16 + 16 + 0 + 6 + 566 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4476711276 + ... + 4476711311.

It is an arithmetic number, because the mean of its divisors is an integer number (29098623411).

Almost surely, 2^161161606566 is an apocalyptic number.

161161606566 is an abundant number, since it is smaller than the sum of its proper divisors (188021874366).

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

161161606566 is a wasteful number, since it uses less digits than its factorization.

161161606566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8953422595 (or 8953422592 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 161161606566 in words is "one hundred sixty-one billion, one hundred sixty-one million, six hundred six thousand, five hundred sixty-six".