20143217 has 4 divisors (see below), whose sum is σ = 20247780. Its totient is φ = 20038656.

The previous prime is 20143171. The next prime is 20143219. The reversal of 20143217 is 71234102.

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 10214416 + 9928801 = 3196^2 + 3151^2 .

It is a cyclic number.

It is not a de Polignac number, because 20143217 - 2⁶ = 20143153 is a prime.

It is a super-2 number, since 2×20143217² = 811498382218178, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20143219) 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, 51992 + ... + 52377.

It is an arithmetic number, because the mean of its divisors is an integer number (5061945).

Almost surely, 2^20143217 is an apocalyptic number.

It is an amenable number.

20143217 is a deficient number, since it is larger than the sum of its proper divisors (104563).

20143217 is a wasteful number, since it uses less digits than its factorization.

20143217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104562.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 20143217 is about 4488.1195394062. The cubic root of 20143217 is about 272.0881391482.

Adding to 20143217 its reverse (71234102), we get a palindrome (91377319).

The spelling of 20143217 in words is "twenty million, one hundred forty-three thousand, two hundred seventeen".