19809472 has 14 divisors (see below), whose sum is σ = 39309548. Its totient is φ = 9904704.

The previous prime is 19809451. The next prime is 19809473. The reversal of 19809472 is 27490891.

It is not an unprimeable number, because it can be changed into a prime (19809473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154698 + ... + 154825.

Almost surely, 2^19809472 is an apocalyptic number.

It is an amenable number.

19809472 is a deficient number, since it is larger than the sum of its proper divisors (19500076).

19809472 is an equidigital number, since it uses as much as digits as its factorization.

19809472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309535 (or 309525 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 19809472 is about 4450.7833018470. The cubic root of 19809472 is about 270.5770557077.

The spelling of 19809472 in words is "nineteen million, eight hundred nine thousand, four hundred seventy-two".