17939387789 has 2 divisors, whose sum is σ = 17939387790. Its totient is φ = 17939387788.

The previous prime is 17939387779. The next prime is 17939387857. The reversal of 17939387789 is 98778393971.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10042044100 + 7897343689 = 100210^2 + 88867^2 .

It is a cyclic number.

It is not a de Polignac number, because 17939387789 - 2¹⁶ = 17939322253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17939387749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8969693894 + 8969693895.

It is an arithmetic number, because the mean of its divisors is an integer number (8969693895).

Almost surely, 2^17939387789 is an apocalyptic number.

It is an amenable number.

17939387789 is a deficient number, since it is larger than the sum of its proper divisors (1).

17939387789 is an equidigital number, since it uses as much as digits as its factorization.

17939387789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144027072, while the sum is 71.

The spelling of 17939387789 in words is "seventeen billion, nine hundred thirty-nine million, three hundred eighty-seven thousand, seven hundred eighty-nine".