161666905177 has 8 divisors (see below), whose sum is σ = 170563342400. Its totient is φ = 152809233264.

The previous prime is 161666905157. The next prime is 161666905187. The reversal of 161666905177 is 771509666161.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161666905177 is a prime.

It is a super-2 number, since 2×161666905177² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161666905157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9682758 + ... + 9699439.

It is an arithmetic number, because the mean of its divisors is an integer number (21320417800).

Almost surely, 2^161666905177 is an apocalyptic number.

It is an amenable number.

161666905177 is a deficient number, since it is larger than the sum of its proper divisors (8896437223).

161666905177 is a wasteful number, since it uses less digits than its factorization.

161666905177 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19382655.

The product of its (nonzero) digits is 2857680, while the sum is 55.

The spelling of 161666905177 in words is "one hundred sixty-one billion, six hundred sixty-six million, nine hundred five thousand, one hundred seventy-seven".