19696321 has 4 divisors (see below), whose sum is σ = 20228692. Its totient is φ = 19163952.

The previous prime is 19696309. The next prime is 19696367. The reversal of 19696321 is 12369691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12369691 = 71 ⋅174221.

It can be written as a sum of positive squares in 2 ways, for example, as 17977600 + 1718721 = 4240^2 + 1311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19696321 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 532333 = 19696321 / (1 + 9 + 6 + 9 + 6 + 3 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19696301) 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, 266130 + ... + 266203.

It is an arithmetic number, because the mean of its divisors is an integer number (5057173).

Almost surely, 2^19696321 is an apocalyptic number.

It is an amenable number.

19696321 is a deficient number, since it is larger than the sum of its proper divisors (532371).

19696321 is an equidigital number, since it uses as much as digits as its factorization.

19696321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532370.

The product of its digits is 17496, while the sum is 37.

The square root of 19696321 is about 4438.0537400982. The cubic root of 19696321 is about 270.0608961866.

The spelling of 19696321 in words is "nineteen million, six hundred ninety-six thousand, three hundred twenty-one".