19928991101 has 2 divisors, whose sum is σ = 19928991102. Its totient is φ = 19928991100.

The previous prime is 19928991067. The next prime is 19928991109. The reversal of 19928991101 is 10119982991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19928968900 + 22201 = 141170^2 + 149^2 .

It is an emirp because it is prime and its reverse (10119982991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19928991101 - 2¹⁰ = 19928990077 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19928991101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19928991109) 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, 9964495550 + 9964495551.

It is an arithmetic number, because the mean of its divisors is an integer number (9964495551).

Almost surely, 2^19928991101 is an apocalyptic number.

It is an amenable number.

19928991101 is a deficient number, since it is larger than the sum of its proper divisors (1).

19928991101 is an equidigital number, since it uses as much as digits as its factorization.

19928991101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 50.

The spelling of 19928991101 in words is "nineteen billion, nine hundred twenty-eight million, nine hundred ninety-one thousand, one hundred one".