67680779 has 2 divisors, whose sum is σ = 67680780. Its totient is φ = 67680778.

The previous prime is 67680763. The next prime is 67680797. The reversal of 67680779 is 97708676.

Together with next prime (67680797) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 67680779 - 2⁴ = 67680763 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (67680749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33840389 + 33840390.

It is an arithmetic number, because the mean of its divisors is an integer number (33840390).

Almost surely, 2^67680779 is an apocalyptic number.

67680779 is a deficient number, since it is larger than the sum of its proper divisors (1).

67680779 is an equidigital number, since it uses as much as digits as its factorization.

67680779 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 889056, while the sum is 50.

The square root of 67680779 is about 8226.8328656902. The cubic root of 67680779 is about 407.5258071402.

The spelling of 67680779 in words is "sixty-seven million, six hundred eighty thousand, seven hundred seventy-nine".