681934823 has 2 divisors, whose sum is σ = 681934824. Its totient is φ = 681934822.

The previous prime is 681934801. The next prime is 681934859. The reversal of 681934823 is 328439186.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 681934823 - 2¹⁰ = 681933799 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681931823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340967411 + 340967412.

It is an arithmetic number, because the mean of its divisors is an integer number (340967412).

Almost surely, 2^681934823 is an apocalyptic number.

681934823 is a deficient number, since it is larger than the sum of its proper divisors (1).

681934823 is an equidigital number, since it uses as much as digits as its factorization.

681934823 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 44.

The square root of 681934823 is about 26113.8818064263. The cubic root of 681934823 is about 880.1991728064.

The spelling of 681934823 in words is "six hundred eighty-one million, nine hundred thirty-four thousand, eight hundred twenty-three".