19806074389 has 2 divisors, whose sum is σ = 19806074390. Its totient is φ = 19806074388.

The previous prime is 19806074377. The next prime is 19806074423. The reversal of 19806074389 is 98347060891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15589520164 + 4216554225 = 124858^2 + 64935^2 .

It is an emirp because it is prime and its reverse (98347060891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19806074389 - 2¹³ = 19806066197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19806074369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9903037194 + 9903037195.

It is an arithmetic number, because the mean of its divisors is an integer number (9903037195).

Almost surely, 2^19806074389 is an apocalyptic number.

It is an amenable number.

19806074389 is a deficient number, since it is larger than the sum of its proper divisors (1).

19806074389 is an equidigital number, since it uses as much as digits as its factorization.

19806074389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2612736, while the sum is 55.

The spelling of 19806074389 in words is "nineteen billion, eight hundred six million, seventy-four thousand, three hundred eighty-nine".