668787866 has 8 divisors (see below), whose sum is σ = 1003389204. Its totient is φ = 334324800.

The previous prime is 668787829. The next prime is 668787869.

668787866 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 474324841 + 194463025 = 21779^2 + 13945^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 668787799 and 668787808.

It is not an unprimeable number, because it can be changed into a prime (668787869) 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 3 ways as a sum of consecutive naturals, for example, 21485 + ... + 42416.

Almost surely, 2^668787866 is an apocalyptic number.

668787866 is a deficient number, since it is larger than the sum of its proper divisors (334601338).

668787866 is a wasteful number, since it uses less digits than its factorization.

668787866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69136.

The product of its digits is 32514048, while the sum is 62.

The square root of 668787866 is about 25860.9332004860. The cubic root of 668787866 is about 874.5060029535.

The spelling of 668787866 in words is "six hundred sixty-eight million, seven hundred eighty-seven thousand, eight hundred sixty-six".