68388972661 has 2 divisors, whose sum is σ = 68388972662. Its totient is φ = 68388972660.

The previous prime is 68388972599. The next prime is 68388972679. The reversal of 68388972661 is 16627988386.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67759213636 + 629759025 = 260306^2 + 25095^2 .

It is a cyclic number.

It is not a de Polignac number, because 68388972661 - 2¹¹ = 68388970613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 68388972593 and 68388972602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68388952661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34194486330 + 34194486331.

It is an arithmetic number, because the mean of its divisors is an integer number (34194486331).

Almost surely, 2^68388972661 is an apocalyptic number.

It is an amenable number.

68388972661 is a deficient number, since it is larger than the sum of its proper divisors (1).

68388972661 is an equidigital number, since it uses as much as digits as its factorization.

68388972661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41803776, while the sum is 64.

The spelling of 68388972661 in words is "sixty-eight billion, three hundred eighty-eight million, nine hundred seventy-two thousand, six hundred sixty-one".