19893217 has 4 divisors (see below), whose sum is σ = 20579220. Its totient is φ = 19207216.

The previous prime is 19893197. The next prime is 19893221. The reversal of 19893217 is 71239891.

19893217 is nontrivially palindromic in base 4.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5216656 + 14676561 = 2284^2 + 3831^2 .

It is a cyclic number.

It is not a de Polignac number, because 19893217 - 2²³ = 11504609 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 19893217.

It is not an unprimeable number, because it can be changed into a prime (19893017) 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, 342958 + ... + 343015.

It is an arithmetic number, because the mean of its divisors is an integer number (5144805).

Almost surely, 2^19893217 is an apocalyptic number.

It is an amenable number.

19893217 is a deficient number, since it is larger than the sum of its proper divisors (686003).

19893217 is an equidigital number, since it uses as much as digits as its factorization.

19893217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686002.

The product of its digits is 27216, while the sum is 40.

The square root of 19893217 is about 4460.1812743430. The cubic root of 19893217 is about 270.9578099106.

The spelling of 19893217 in words is "nineteen million, eight hundred ninety-three thousand, two hundred seventeen".