19949909 has 12 divisors (see below), whose sum is σ = 23294304. Its totient is φ = 17085516.

The previous prime is 19949899. The next prime is 19949911. The reversal of 19949909 is 90994991.

It is a de Polignac number, because none of the positive numbers 2^k-19949909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19949929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16214 + ... + 17400.

It is an arithmetic number, because the mean of its divisors is an integer number (1941192).

Almost surely, 2^19949909 is an apocalyptic number.

It is an amenable number.

19949909 is a deficient number, since it is larger than the sum of its proper divisors (3344395).

19949909 is an frugal number, since it uses more digits than its factorization.

19949909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222 (or 1194 counting only the distinct ones).

The product of its (nonzero) digits is 236196, while the sum is 50.

The square root of 19949909 is about 4466.5320999630. The cubic root of 19949909 is about 271.2149590531.

The spelling of 19949909 in words is "nineteen million, nine hundred forty-nine thousand, nine hundred nine".