20840675761 has 2 divisors, whose sum is σ = 20840675762. Its totient is φ = 20840675760.

The previous prime is 20840675731. The next prime is 20840675771. The reversal of 20840675761 is 16757604802.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13760463025 + 7080212736 = 117305^2 + 84144^2 .

It is a cyclic number.

It is not a de Polignac number, because 20840675761 - 2⁹ = 20840675249 is a prime.

It is not a weakly prime, because it can be changed into another prime (20840675701) 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, 10420337880 + 10420337881.

It is an arithmetic number, because the mean of its divisors is an integer number (10420337881).

Almost surely, 2^20840675761 is an apocalyptic number.

It is an amenable number.

20840675761 is a deficient number, since it is larger than the sum of its proper divisors (1).

20840675761 is an equidigital number, since it uses as much as digits as its factorization.

20840675761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 564480, while the sum is 46.

The spelling of 20840675761 in words is "twenty billion, eight hundred forty million, six hundred seventy-five thousand, seven hundred sixty-one".