19685822017 has 2 divisors, whose sum is σ = 19685822018. Its totient is φ = 19685822016.

The previous prime is 19685821999. The next prime is 19685822053. The reversal of 19685822017 is 71022858691.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18879034801 + 806787216 = 137401^2 + 28404^2 .

It is a cyclic number.

It is not a de Polignac number, because 19685822017 - 2¹⁹ = 19685297729 is a prime.

It is not a weakly prime, because it can be changed into another prime (19685822077) 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, 9842911008 + 9842911009.

It is an arithmetic number, because the mean of its divisors is an integer number (9842911009).

Almost surely, 2^19685822017 is an apocalyptic number.

It is an amenable number.

19685822017 is a deficient number, since it is larger than the sum of its proper divisors (1).

19685822017 is an equidigital number, since it uses as much as digits as its factorization.

19685822017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 483840, while the sum is 49.

The spelling of 19685822017 in words is "nineteen billion, six hundred eighty-five million, eight hundred twenty-two thousand, seventeen".