19909684 has 6 divisors (see below), whose sum is σ = 34841954. Its totient is φ = 9954840.

The previous prime is 19909679. The next prime is 19909691. The reversal of 19909684 is 48690991.

It can be written as a sum of positive squares in only one way, i.e., 19607184 + 302500 = 4428^2 + 550^2 .

It is a congruent number.

It is an unprimeable number.

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, 2488707 + ... + 2488714.

Almost surely, 2^19909684 is an apocalyptic number.

It is an amenable number.

19909684 is a deficient number, since it is larger than the sum of its proper divisors (14932270).

19909684 is a wasteful number, since it uses less digits than its factorization.

19909684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4977425 (or 4977423 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The square root of 19909684 is about 4462.0268936886. The cubic root of 19909684 is about 271.0325528358.

The spelling of 19909684 in words is "nineteen million, nine hundred nine thousand, six hundred eighty-four".