681838049 has 2 divisors, whose sum is σ = 681838050. Its totient is φ = 681838048.

The previous prime is 681838039. The next prime is 681838067. The reversal of 681838049 is 940838186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 518381824 + 163456225 = 22768^2 + 12785^2 .

It is a cyclic number.

It is not a de Polignac number, because 681838049 - 2²⁸ = 413402593 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 681837994 and 681838012.

It is not a weakly prime, because it can be changed into another prime (681838039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340919024 + 340919025.

It is an arithmetic number, because the mean of its divisors is an integer number (340919025).

Almost surely, 2^681838049 is an apocalyptic number.

It is an amenable number.

681838049 is a deficient number, since it is larger than the sum of its proper divisors (1).

681838049 is an equidigital number, since it uses as much as digits as its factorization.

681838049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 331776, while the sum is 47.

The square root of 681838049 is about 26112.0288181520. The cubic root of 681838049 is about 880.1575342111.

The spelling of 681838049 in words is "six hundred eighty-one million, eight hundred thirty-eight thousand, forty-nine".