161666512 has 40 divisors (see below), whose sum is σ = 359724992. Its totient is φ = 68947200.

The previous prime is 161666509. The next prime is 161666543. The reversal of 161666512 is 215666161.

It is a happy number.

It is a super-2 number, since 2×161666512² = 52272122204492288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20212 + ... + 27052.

Almost surely, 2^161666512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161666512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179862496).

161666512 is an abundant number, since it is smaller than the sum of its proper divisors (198058480).

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

161666512 is a wasteful number, since it uses less digits than its factorization.

161666512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7067 (or 7061 counting only the distinct ones).

The product of its digits is 12960, while the sum is 34.

The square root of 161666512 is about 12714.8146663646. The cubic root of 161666512 is about 544.7618542627.

The spelling of 161666512 in words is "one hundred sixty-one million, six hundred sixty-six thousand, five hundred twelve".