680868666 has 40 divisors (see below), whose sum is σ = 1615400820. Its totient is φ = 213604992.

The previous prime is 680868659. The next prime is 680868677. The reversal of 680868666 is 666868086.

680868666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 672313041 + 8555625 = 25929^2 + 2925^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 120861 + ... + 126368.

Almost surely, 2^680868666 is an apocalyptic number.

680868666 is an abundant number, since it is smaller than the sum of its proper divisors (934532154).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

680868666 is a wasteful number, since it uses less digits than its factorization.

680868666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247260 (or 247251 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 54.

The square root of 680868666 is about 26093.4602151574. The cubic root of 680868666 is about 879.7402237692.

The spelling of 680868666 in words is "six hundred eighty million, eight hundred sixty-eight thousand, six hundred sixty-six".