668310081 has 4 divisors (see below), whose sum is σ = 891080112. Its totient is φ = 445540052.

The previous prime is 668310079. The next prime is 668310113. The reversal of 668310081 is 180013866.

668310081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 668310081 - 2¹ = 668310079 is a prime.

It is a super-2 number, since 2×668310081² = 893276728732453122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668310281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111385011 + ... + 111385016.

It is an arithmetic number, because the mean of its divisors is an integer number (222770028).

Almost surely, 2^668310081 is an apocalyptic number.

It is an amenable number.

668310081 is a deficient number, since it is larger than the sum of its proper divisors (222770031).

668310081 is a wasteful number, since it uses less digits than its factorization.

668310081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222770030.

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 668310081 is about 25851.6939677074. The cubic root of 668310081 is about 874.2977030274.

The spelling of 668310081 in words is "six hundred sixty-eight million, three hundred ten thousand, eighty-one".