19718445601 has 2 divisors, whose sum is σ = 19718445602. Its totient is φ = 19718445600.

The previous prime is 19718445599. The next prime is 19718445611. The reversal of 19718445601 is 10654481791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18975338001 + 743107600 = 137751^2 + 27260^2 .

It is a cyclic number.

It is not a de Polignac number, because 19718445601 - 2¹ = 19718445599 is a prime.

Together with 19718445599, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (19718445611) 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, 9859222800 + 9859222801.

It is an arithmetic number, because the mean of its divisors is an integer number (9859222801).

Almost surely, 2^19718445601 is an apocalyptic number.

It is an amenable number.

19718445601 is a deficient number, since it is larger than the sum of its proper divisors (1).

19718445601 is an equidigital number, since it uses as much as digits as its factorization.

19718445601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 241920, while the sum is 46.

The spelling of 19718445601 in words is "nineteen billion, seven hundred eighteen million, four hundred forty-five thousand, six hundred one".