19649389 has 2 divisors, whose sum is σ = 19649390. Its totient is φ = 19649388.

The previous prime is 19649369. The next prime is 19649393. The reversal of 19649389 is 98394691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12180100 + 7469289 = 3490^2 + 2733^2 .

It is a cyclic number.

It is not a de Polignac number, because 19649389 - 2⁷ = 19649261 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19649309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9824694 + 9824695.

It is an arithmetic number, because the mean of its divisors is an integer number (9824695).

Almost surely, 2^19649389 is an apocalyptic number.

It is an amenable number.

19649389 is a deficient number, since it is larger than the sum of its proper divisors (1).

19649389 is an equidigital number, since it uses as much as digits as its factorization.

19649389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 419904, while the sum is 49.

The square root of 19649389 is about 4432.7631337575. The cubic root of 19649389 is about 269.8462270246.

The spelling of 19649389 in words is "nineteen million, six hundred forty-nine thousand, three hundred eighty-nine".