668685081 has 8 divisors (see below), whose sum is σ = 898088544. Its totient is φ = 442535840.

The previous prime is 668685077. The next prime is 668685091. The reversal of 668685081 is 180586866.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 668685081 - 2² = 668685077 is a prime.

It is a super-2 number, since 2×668685081² = 894279475103953122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 668685081.

It is not an unprimeable number, because it can be changed into a prime (668685011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 813075 + ... + 813896.

It is an arithmetic number, because the mean of its divisors is an integer number (112261068).

Almost surely, 2^668685081 is an apocalyptic number.

It is an amenable number.

668685081 is a deficient number, since it is larger than the sum of its proper divisors (229403463).

668685081 is a wasteful number, since it uses less digits than its factorization.

668685081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1627111.

The product of its (nonzero) digits is 552960, while the sum is 48.

The square root of 668685081 is about 25858.9458601854. The cubic root of 668685081 is about 874.4612001546.

The spelling of 668685081 in words is "six hundred sixty-eight million, six hundred eighty-five thousand, eighty-one".