168591680729 has 2 divisors, whose sum is σ = 168591680730. Its totient is φ = 168591680728.

The previous prime is 168591680711. The next prime is 168591680731. The reversal of 168591680729 is 927086195861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 150299659225 + 18292021504 = 387685^2 + 135248^2 .

It is a cyclic number.

It is not a de Polignac number, because 168591680729 - 2⁸ = 168591680473 is a prime.

It is a super-2 number, since 2×168591680729² (a number of 23 digits) contains 22 as substring.

Together with 168591680731, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (168591680759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84295840364 + 84295840365.

It is an arithmetic number, because the mean of its divisors is an integer number (84295840365).

Almost surely, 2^168591680729 is an apocalyptic number.

It is an amenable number.

168591680729 is a deficient number, since it is larger than the sum of its proper divisors (1).

168591680729 is an equidigital number, since it uses as much as digits as its factorization.

168591680729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13063680, while the sum is 62.

The spelling of 168591680729 in words is "one hundred sixty-eight billion, five hundred ninety-one million, six hundred eighty thousand, seven hundred twenty-nine".