681963859 has 2 divisors, whose sum is σ = 681963860. Its totient is φ = 681963858.

The previous prime is 681963853. The next prime is 681963881. The reversal of 681963859 is 958369186.

It is a happy number.

681963859 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 681963859 - 2³ = 681963851 is a prime.

It is not a weakly prime, because it can be changed into another prime (681963851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340981929 + 340981930.

It is an arithmetic number, because the mean of its divisors is an integer number (340981930).

Almost surely, 2^681963859 is an apocalyptic number.

681963859 is a deficient number, since it is larger than the sum of its proper divisors (1).

681963859 is an equidigital number, since it uses as much as digits as its factorization.

681963859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2799360, while the sum is 55.

The square root of 681963859 is about 26114.4377500263. The cubic root of 681963859 is about 880.2116652517.

The spelling of 681963859 in words is "six hundred eighty-one million, nine hundred sixty-three thousand, eight hundred fifty-nine".