68657791 has 2 divisors, whose sum is σ = 68657792. Its totient is φ = 68657790.

The previous prime is 68657789. The next prime is 68657801. The reversal of 68657791 is 19775686.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 68657791 - 2¹ = 68657789 is a prime.

Together with 68657789, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68657731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34328895 + 34328896.

It is an arithmetic number, because the mean of its divisors is an integer number (34328896).

Almost surely, 2^68657791 is an apocalyptic number.

68657791 is a deficient number, since it is larger than the sum of its proper divisors (1).

68657791 is an equidigital number, since it uses as much as digits as its factorization.

68657791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 635040, while the sum is 49.

The square root of 68657791 is about 8285.9996982863. Note that the first 3 decimals coincide. The cubic root of 68657791 is about 409.4774047643.

The spelling of 68657791 in words is "sixty-eight million, six hundred fifty-seven thousand, seven hundred ninety-one".