668476861 has 8 divisors (see below), whose sum is σ = 720158040. Its totient is φ = 616832832.

The previous prime is 668476793. The next prime is 668476871. The reversal of 668476861 is 168674866.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 316163961 + 352312900 = 17781^2 + 18770^2 .

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 668476861 - 2⁹ = 668476349 is a prime.

It is a super-2 number, since 2×668476861² = 893722627384826642, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 668476799 and 668476808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668476871) 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, 36471 + ... + 51643.

It is an arithmetic number, because the mean of its divisors is an integer number (90019755).

Almost surely, 2^668476861 is an apocalyptic number.

It is an amenable number.

668476861 is a deficient number, since it is larger than the sum of its proper divisors (51681179).

668476861 is a wasteful number, since it uses less digits than its factorization.

668476861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18575.

The product of its digits is 2322432, while the sum is 52.

The square root of 668476861 is about 25854.9194738642. The cubic root of 668476861 is about 874.3704253795.

The spelling of 668476861 in words is "six hundred sixty-eight million, four hundred seventy-six thousand, eight hundred sixty-one".