19965699553 has 2 divisors, whose sum is σ = 19965699554. Its totient is φ = 19965699552.

The previous prime is 19965699527. The next prime is 19965699557. The reversal of 19965699553 is 35599656991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14264241489 + 5701458064 = 119433^2 + 75508^2 .

It is a cyclic number.

It is not a de Polignac number, because 19965699553 - 2⁹ = 19965699041 is a prime.

It is not a weakly prime, because it can be changed into another prime (19965699557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9982849776 + 9982849777.

It is an arithmetic number, because the mean of its divisors is an integer number (9982849777).

Almost surely, 2^19965699553 is an apocalyptic number.

It is an amenable number.

19965699553 is a deficient number, since it is larger than the sum of its proper divisors (1).

19965699553 is an equidigital number, since it uses as much as digits as its factorization.

19965699553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 88573500, while the sum is 67.

It can be divided in two parts, 199656 and 99553, that added together give a square (299209 = 547²).

The spelling of 19965699553 in words is "nineteen billion, nine hundred sixty-five million, six hundred ninety-nine thousand, five hundred fifty-three".