168685668 has 18 divisors (see below), whose sum is σ = 426399974. Its totient is φ = 56228544.

The previous prime is 168685651. The next prime is 168685669. The reversal of 168685668 is 866586861.

It is a happy number.

168685668 is a `hidden beast` number, since 16 + 8 + 68 + 566 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 141562404 + 27123264 = 11898^2 + 5208^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (168685669) 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, 2342821 + ... + 2342892.

Almost surely, 2^168685668 is an apocalyptic number.

168685668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

168685668 is an abundant number, since it is smaller than the sum of its proper divisors (257714306).

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

168685668 is a wasteful number, since it uses less digits than its factorization.

168685668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4685723 (or 4685718 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 54.

The square root of 168685668 is about 12987.9046808945. The cubic root of 168685668 is about 552.5344933182.

The spelling of 168685668 in words is "one hundred sixty-eight million, six hundred eighty-five thousand, six hundred sixty-eight".