19629809 has 4 divisors (see below), whose sum is σ = 19643904. Its totient is φ = 19615716.

The previous prime is 19629803. The next prime is 19629821. The reversal of 19629809 is 90892691.

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.

It is a cyclic number.

It is not a de Polignac number, because 19629809 - 2¹⁶ = 19564273 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19629809.

It is not an unprimeable number, because it can be changed into a prime (19629803) 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, 4697 + ... + 7830.

It is an arithmetic number, because the mean of its divisors is an integer number (4910976).

Almost surely, 2^19629809 is an apocalyptic number.

It is an amenable number.

19629809 is a deficient number, since it is larger than the sum of its proper divisors (14095).

19629809 is a wasteful number, since it uses less digits than its factorization.

19629809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14094.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 19629809 is about 4430.5540285612. The cubic root of 19629809 is about 269.7565661353.

The spelling of 19629809 in words is "nineteen million, six hundred twenty-nine thousand, eight hundred nine".