68660491 has 2 divisors, whose sum is σ = 68660492. Its totient is φ = 68660490.

The previous prime is 68660477. The next prime is 68660503. The reversal of 68660491 is 19406686.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 68660491 - 2¹³ = 68652299 is a prime.

It is a super-2 number, since 2×68660491² = 9428526048722162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68660191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34330245 + 34330246.

It is an arithmetic number, because the mean of its divisors is an integer number (34330246).

Almost surely, 2^68660491 is an apocalyptic number.

68660491 is a deficient number, since it is larger than the sum of its proper divisors (1).

68660491 is an equidigital number, since it uses as much as digits as its factorization.

68660491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 68660491 is about 8286.1626221068. The cubic root of 68660491 is about 409.4827723246.

The spelling of 68660491 in words is "sixty-eight million, six hundred sixty thousand, four hundred ninety-one".