678586891 has 2 divisors, whose sum is σ = 678586892. Its totient is φ = 678586890.

The previous prime is 678586879. The next prime is 678586949. The reversal of 678586891 is 198685876.

It is an a-pointer prime, because the next prime (678586949) can be obtained adding 678586891 to its sum of digits (58).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 678586891 - 2¹⁹ = 678062603 is a prime.

It is not a weakly prime, because it can be changed into another prime (678586801) 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, 339293445 + 339293446.

It is an arithmetic number, because the mean of its divisors is an integer number (339293446).

Almost surely, 2^678586891 is an apocalyptic number.

678586891 is a deficient number, since it is larger than the sum of its proper divisors (1).

678586891 is an equidigital number, since it uses as much as digits as its factorization.

678586891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5806080, while the sum is 58.

The square root of 678586891 is about 26049.7004013482. The cubic root of 678586891 is about 878.7563747803.

The spelling of 678586891 in words is "six hundred seventy-eight million, five hundred eighty-six thousand, eight hundred ninety-one".