68615600644 has 6 divisors (see below), whose sum is σ = 120077301134. Its totient is φ = 34307800320.

The previous prime is 68615600639. The next prime is 68615600687. The reversal of 68615600644 is 44600651686.

It can be written as a sum of positive squares in only one way, i.e., 68492124100 + 123476544 = 261710^2 + 11112^2 .

It is a junction number, because it is equal to n+sod(n) for n = 68615600594 and 68615600603.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8576950077 + ... + 8576950084.

Almost surely, 2^68615600644 is an apocalyptic number.

It is an amenable number.

68615600644 is a deficient number, since it is larger than the sum of its proper divisors (51461700490).

68615600644 is a wasteful number, since it uses less digits than its factorization.

68615600644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17153900165 (or 17153900163 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 46.

The spelling of 68615600644 in words is "sixty-eight billion, six hundred fifteen million, six hundred thousand, six hundred forty-four".