681097041949 has 2 divisors, whose sum is σ = 681097041950. Its totient is φ = 681097041948.

The previous prime is 681097041917. The next prime is 681097041953. The reversal of 681097041949 is 949140790186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 646689388900 + 34407653049 = 804170^2 + 185493^2 .

It is a cyclic number.

It is not a de Polignac number, because 681097041949 - 2⁵ = 681097041917 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 681097041893 and 681097041902.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681097041979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340548520974 + 340548520975.

It is an arithmetic number, because the mean of its divisors is an integer number (340548520975).

Almost surely, 2^681097041949 is an apocalyptic number.

It is an amenable number.

681097041949 is a deficient number, since it is larger than the sum of its proper divisors (1).

681097041949 is an equidigital number, since it uses as much as digits as its factorization.

681097041949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3919104, while the sum is 58.

The spelling of 681097041949 in words is "six hundred eighty-one billion, ninety-seven million, forty-one thousand, nine hundred forty-nine".