19903109 has 4 divisors (see below), whose sum is σ = 20366016. Its totient is φ = 19440204.

The previous prime is 19903097. The next prime is 19903129. The reversal of 19903109 is 90130991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90130991 = 17 ⋅5301823.

It is a cyclic number.

It is not a de Polignac number, because 19903109 - 2⁸ = 19902853 is a prime.

It is a super-2 number, since 2×19903109² = 792267495731762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19903129) 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 in 3 ways as a sum of consecutive naturals, for example, 231389 + ... + 231474.

It is an arithmetic number, because the mean of its divisors is an integer number (5091504).

Almost surely, 2^19903109 is an apocalyptic number.

It is an amenable number.

19903109 is a deficient number, since it is larger than the sum of its proper divisors (462907).

19903109 is an equidigital number, since it uses as much as digits as its factorization.

19903109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462906.

The product of its (nonzero) digits is 2187, while the sum is 32.

The square root of 19903109 is about 4461.2900600611. The cubic root of 19903109 is about 271.0027141697.

The spelling of 19903109 in words is "nineteen million, nine hundred three thousand, one hundred nine".