19995779599 has 2 divisors, whose sum is σ = 19995779600. Its totient is φ = 19995779598.

The previous prime is 19995779567. The next prime is 19995779651. The reversal of 19995779599 is 99597759991.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (99597759991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19995779599 - 2⁵ = 19995779567 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19995779509) 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, 9997889799 + 9997889800.

It is an arithmetic number, because the mean of its divisors is an integer number (9997889800).

Almost surely, 2^19995779599 is an apocalyptic number.

19995779599 is a deficient number, since it is larger than the sum of its proper divisors (1).

19995779599 is an equidigital number, since it uses as much as digits as its factorization.

19995779599 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 651015225, while the sum is 79.

The spelling of 19995779599 in words is "nineteen billion, nine hundred ninety-five million, seven hundred seventy-nine thousand, five hundred ninety-nine".