161666586 has 24 divisors (see below), whose sum is σ = 365508000. Its totient is φ = 51545736.

The previous prime is 161666569. The next prime is 161666599. The reversal of 161666586 is 685666161.

It is a super-2 number, since 2×161666586² = 52272170057790792, which contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 194836 + ... + 195663.

It is an arithmetic number, because the mean of its divisors is an integer number (15229500).

Almost surely, 2^161666586 is an apocalyptic number.

161666586 is an abundant number, since it is smaller than the sum of its proper divisors (203841414).

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

161666586 is a wasteful number, since it uses less digits than its factorization.

161666586 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390530 (or 390527 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 161666586 is about 12714.8175763555. The cubic root of 161666586 is about 544.7619373810.

The spelling of 161666586 in words is "one hundred sixty-one million, six hundred sixty-six thousand, five hundred eighty-six".