42728650681 has 2 divisors, whose sum is σ = 42728650682. Its totient is φ = 42728650680.

The previous prime is 42728650609. The next prime is 42728650717. The reversal of 42728650681 is 18605682724.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42728610681 + 40000 = 206709^2 + 200^2 .

It is a cyclic number.

It is not a de Polignac number, because 42728650681 - 2⁷ = 42728650553 is a prime.

It is a super-2 number, since 2×42728650681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (42728650781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21364325340 + 21364325341.

It is an arithmetic number, because the mean of its divisors is an integer number (21364325341).

Almost surely, 2^42728650681 is an apocalyptic number.

It is an amenable number.

42728650681 is a deficient number, since it is larger than the sum of its proper divisors (1).

42728650681 is an equidigital number, since it uses as much as digits as its factorization.

42728650681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1290240, while the sum is 49.

The spelling of 42728650681 in words is "forty-two billion, seven hundred twenty-eight million, six hundred fifty thousand, six hundred eighty-one".