19698109 has 2 divisors, whose sum is σ = 19698110. Its totient is φ = 19698108.

The previous prime is 19698083. The next prime is 19698127. The reversal of 19698109 is 90189691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13118884 + 6579225 = 3622^2 + 2565^2 .

It is a cyclic number.

It is not a de Polignac number, because 19698109 - 2⁹ = 19697597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19698179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9849054 + 9849055.

It is an arithmetic number, because the mean of its divisors is an integer number (9849055).

Almost surely, 2^19698109 is an apocalyptic number.

It is an amenable number.

19698109 is a deficient number, since it is larger than the sum of its proper divisors (1).

19698109 is an equidigital number, since it uses as much as digits as its factorization.

19698109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 19698109 is about 4438.2551751786. The cubic root of 19698109 is about 270.0690678357.

The spelling of 19698109 in words is "nineteen million, six hundred ninety-eight thousand, one hundred nine".