668675811076 has 81 divisors (see below), whose sum is σ = 1474325895231. Its totient is φ = 264472213824.

The previous prime is 668675811053. The next prime is 668675811077. The reversal of 668675811076 is 670118576866.

It is a happy number.

The square root of 668675811076 is 817726.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 72321193476 + 596354617600 = 268926^2 + 772240^2 .

It is not an unprimeable number, because it can be changed into a prime (668675811077) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 148823886 + ... + 148828378.

Almost surely, 2^668675811076 is an apocalyptic number.

668675811076 is the 817726-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668675811076

668675811076 is an abundant number, since it is smaller than the sum of its proper divisors (805650084155).

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

668675811076 is an equidigital number, since it uses as much as digits as its factorization.

668675811076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9030 (or 4515 counting only the distinct ones).

The product of its (nonzero) digits is 20321280, while the sum is 61.

The spelling of 668675811076 in words is "six hundred sixty-eight billion, six hundred seventy-five million, eight hundred eleven thousand, seventy-six".