19903139 has 4 divisors (see below), whose sum is σ = 20108424. Its totient is φ = 19697856.

The previous prime is 19903129. The next prime is 19903153. The reversal of 19903139 is 93130991.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19903139 - 2¹² = 19899043 is a prime.

It is a super-3 number, since 3×19903139³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19903099 and 19903108.

It is not an unprimeable number, because it can be changed into a prime (19903129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102497 + ... + 102690.

It is an arithmetic number, because the mean of its divisors is an integer number (5027106).

Almost surely, 2^19903139 is an apocalyptic number.

19903139 is a deficient number, since it is larger than the sum of its proper divisors (205285).

19903139 is an equidigital number, since it uses as much as digits as its factorization.

19903139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205284.

The product of its (nonzero) digits is 6561, while the sum is 35.

The square root of 19903139 is about 4461.2934223160. The cubic root of 19903139 is about 271.0028503306.

The spelling of 19903139 in words is "nineteen million, nine hundred three thousand, one hundred thirty-nine".