19896805 has 4 divisors (see below), whose sum is σ = 23876172. Its totient is φ = 15917440.

The previous prime is 19896707. The next prime is 19896809. The reversal of 19896805 is 50869891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50869891 = 349 ⋅145759.

It can be written as a sum of positive squares in 2 ways, for example, as 13089924 + 6806881 = 3618^2 + 2609^2 .

It is not a de Polignac number, because 19896805 - 2¹¹ = 19894757 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 (19896809) 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, 1989676 + ... + 1989685.

It is an arithmetic number, because the mean of its divisors is an integer number (5969043).

Almost surely, 2^19896805 is an apocalyptic number.

It is an amenable number.

19896805 is a deficient number, since it is larger than the sum of its proper divisors (3979367).

19896805 is an equidigital number, since it uses as much as digits as its factorization.

19896805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3979366.

The product of its (nonzero) digits is 155520, while the sum is 46.

The square root of 19896805 is about 4460.5834820122. The cubic root of 19896805 is about 270.9740991844.

The spelling of 19896805 in words is "nineteen million, eight hundred ninety-six thousand, eight hundred five".