68581477618 has 4 divisors (see below), whose sum is σ = 102872216430. Its totient is φ = 34290738808.

The previous prime is 68581477609. The next prime is 68581477619. The reversal of 68581477618 is 81677418586.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81677418586 = 2 ⋅40838709293.

It can be written as a sum of positive squares in only one way, i.e., 64980637569 + 3600840049 = 254913^2 + 60007^2 .

It is not an unprimeable number, because it can be changed into a prime (68581477619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17145369403 + ... + 17145369406.

Almost surely, 2^68581477618 is an apocalyptic number.

68581477618 is a deficient number, since it is larger than the sum of its proper divisors (34290738812).

68581477618 is a wasteful number, since it uses less digits than its factorization.

68581477618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34290738811.

The product of its digits is 18063360, while the sum is 61.

The spelling of 68581477618 in words is "sixty-eight billion, five hundred eighty-one million, four hundred seventy-seven thousand, six hundred eighteen".