68981576638517 has 2 divisors, whose sum is σ = 68981576638518. Its totient is φ = 68981576638516.

The previous prime is 68981576638453. The next prime is 68981576638523. The reversal of 68981576638517 is 71583667518986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66349349451121 + 2632227187396 = 8145511^2 + 1622414^2 .

It is a cyclic number.

It is not a de Polignac number, because 68981576638517 - 2⁶ = 68981576638453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68981576638567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34490788319258 + 34490788319259.

It is an arithmetic number, because the mean of its divisors is an integer number (34490788319259).

Almost surely, 2^{68981576638517} is an apocalyptic number.

It is an amenable number.

68981576638517 is a deficient number, since it is larger than the sum of its proper divisors (1).

68981576638517 is an equidigital number, since it uses as much as digits as its factorization.

68981576638517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3657830400, while the sum is 80.

The spelling of 68981576638517 in words is "sixty-eight trillion, nine hundred eighty-one billion, five hundred seventy-six million, six hundred thirty-eight thousand, five hundred seventeen".