19644698813 has 2 divisors, whose sum is σ = 19644698814. Its totient is φ = 19644698812.

The previous prime is 19644698783. The next prime is 19644698833. The reversal of 19644698813 is 31889644691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17182752889 + 2461945924 = 131083^2 + 49618^2 .

It is a cyclic number.

It is not a de Polignac number, because 19644698813 - 2¹⁴ = 19644682429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19644698833) 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, 9822349406 + 9822349407.

It is an arithmetic number, because the mean of its divisors is an integer number (9822349407).

Almost surely, 2^19644698813 is an apocalyptic number.

It is an amenable number.

19644698813 is a deficient number, since it is larger than the sum of its proper divisors (1).

19644698813 is an equidigital number, since it uses as much as digits as its factorization.

19644698813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8957952, while the sum is 59.

The spelling of 19644698813 in words is "nineteen billion, six hundred forty-four million, six hundred ninety-eight thousand, eight hundred thirteen".