681599839 has 2 divisors, whose sum is σ = 681599840. Its totient is φ = 681599838.

The previous prime is 681599827. The next prime is 681599851. The reversal of 681599839 is 938995186.

It is a balanced prime because it is at equal distance from previous prime (681599827) and next prime (681599851).

It is a cyclic number.

It is not a de Polignac number, because 681599839 - 2²⁷ = 547382111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681599869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340799919 + 340799920.

It is an arithmetic number, because the mean of its divisors is an integer number (340799920).

Almost surely, 2^681599839 is an apocalyptic number.

681599839 is a deficient number, since it is larger than the sum of its proper divisors (1).

681599839 is an equidigital number, since it uses as much as digits as its factorization.

681599839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4199040, while the sum is 58.

The square root of 681599839 is about 26107.4671119203. The cubic root of 681599839 is about 880.0550236772.

The spelling of 681599839 in words is "six hundred eighty-one million, five hundred ninety-nine thousand, eight hundred thirty-nine".