668676859 has 2 divisors, whose sum is σ = 668676860. Its totient is φ = 668676858.

The previous prime is 668676857. The next prime is 668676917. The reversal of 668676859 is 958676866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668676859 - 2¹ = 668676857 is a prime.

It is a super-3 number, since 3×668676859³ (a number of 27 digits) contains 333 as substring.

Together with 668676857, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 668676797 and 668676806.

It is not a weakly prime, because it can be changed into another prime (668676857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334338429 + 334338430.

It is an arithmetic number, because the mean of its divisors is an integer number (334338430).

Almost surely, 2^668676859 is an apocalyptic number.

668676859 is a deficient number, since it is larger than the sum of its proper divisors (1).

668676859 is an equidigital number, since it uses as much as digits as its factorization.

668676859 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26127360, while the sum is 61.

The square root of 668676859 is about 25858.7868818319. The cubic root of 668676859 is about 874.4576160811.

The spelling of 668676859 in words is "six hundred sixty-eight million, six hundred seventy-six thousand, eight hundred fifty-nine".