19664896 has 26 divisors (see below), whose sum is σ = 39333182. Its totient is φ = 9830400.

The previous prime is 19664893. The next prime is 19664899. The reversal of 19664896 is 69846691.

It is an interprime number because it is at equal distance from previous prime (19664893) and next prime (19664899).

It can be written as a sum of positive squares in only one way, i.e., 17305600 + 2359296 = 4160^2 + 1536^2 .

It is not an unprimeable number, because it can be changed into a prime (19664893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1696 + ... + 6496.

Almost surely, 2^19664896 is an apocalyptic number.

19664896 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19664896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19666591).

19664896 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19664896 is an frugal number, since it uses more digits than its factorization.

19664896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4825 (or 4803 counting only the distinct ones).

The product of its digits is 559872, while the sum is 49.

The square root of 19664896 is about 4434.5119235379. The cubic root of 19664896 is about 269.9171945432.

The spelling of 19664896 in words is "nineteen million, six hundred sixty-four thousand, eight hundred ninety-six".