168287661 has 6 divisors (see below), whose sum is σ = 243082190. Its totient is φ = 112191768.

The previous prime is 168287659. The next prime is 168287663. The reversal of 168287661 is 166782861.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (168287659) and next prime (168287663).

It can be written as a sum of positive squares in only one way, i.e., 160503561 + 7784100 = 12669^2 + 2790^2 .

It is not a de Polignac number, because 168287661 - 2¹ = 168287659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168287663) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9349306 + ... + 9349323.

Almost surely, 2^168287661 is an apocalyptic number.

It is an amenable number.

168287661 is a deficient number, since it is larger than the sum of its proper divisors (74794529).

168287661 is a wasteful number, since it uses less digits than its factorization.

168287661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18698635 (or 18698632 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 168287661 is about 12972.5734147084. The cubic root of 168287661 is about 552.0995901755.

The spelling of 168287661 in words is "one hundred sixty-eight million, two hundred eighty-seven thousand, six hundred sixty-one".