19423718789 has 2 divisors, whose sum is σ = 19423718790. Its totient is φ = 19423718788.

The previous prime is 19423718779. The next prime is 19423718827. The reversal of 19423718789 is 98781732491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17624686564 + 1799032225 = 132758^2 + 42415^2 .

It is a cyclic number.

It is not a de Polignac number, because 19423718789 - 2¹² = 19423714693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19423718779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9711859394 + 9711859395.

It is an arithmetic number, because the mean of its divisors is an integer number (9711859395).

Almost surely, 2^19423718789 is an apocalyptic number.

It is an amenable number.

19423718789 is a deficient number, since it is larger than the sum of its proper divisors (1).

19423718789 is an equidigital number, since it uses as much as digits as its factorization.

19423718789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6096384, while the sum is 59.

The spelling of 19423718789 in words is "nineteen billion, four hundred twenty-three million, seven hundred eighteen thousand, seven hundred eighty-nine".