161668689 has 48 divisors (see below), whose sum is σ = 278853120. Its totient is φ = 82494720.

The previous prime is 161668667. The next prime is 161668721. The reversal of 161668689 is 986866161.

161668689 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 161668689 - 2¹¹ = 161666641 is a prime.

It is a super-2 number, since 2×161668689² = 52273530005957442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161668189) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 57877 + ... + 60605.

It is an arithmetic number, because the mean of its divisors is an integer number (5809440).

Almost surely, 2^161668689 is an apocalyptic number.

It is an amenable number.

161668689 is a deficient number, since it is larger than the sum of its proper divisors (117184431).

161668689 is a wasteful number, since it uses less digits than its factorization.

161668689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2790 (or 2783 counting only the distinct ones).

The product of its digits is 746496, while the sum is 51.

The square root of 161668689 is about 12714.9002748744. The cubic root of 161668689 is about 544.7642995047.

The spelling of 161668689 in words is "one hundred sixty-one million, six hundred sixty-eight thousand, six hundred eighty-nine".