221530321730217 has 16 divisors (see below), whose sum is σ = 295610174963712. Its totient is φ = 147568689697680.

The previous prime is 221530321730203. The next prime is 221530321730273. The reversal of 221530321730217 is 712037123035122.

It is not a de Polignac number, because 221530321730217 - 2¹⁰ = 221530321729193 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221530321730287) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57986598 + ... + 61688784.

It is an arithmetic number, because the mean of its divisors is an integer number (18475635935232).

Almost surely, 2^{221530321730217} is an apocalyptic number.

It is an amenable number.

221530321730217 is a deficient number, since it is larger than the sum of its proper divisors (74079853233495).

221530321730217 is a wasteful number, since it uses less digits than its factorization.

221530321730217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3718148.

The product of its (nonzero) digits is 105840, while the sum is 39.

Adding to 221530321730217 its reverse (712037123035122), we get a palindrome (933567444765339).

The spelling of 221530321730217 in words is "two hundred twenty-one trillion, five hundred thirty billion, three hundred twenty-one million, seven hundred thirty thousand, two hundred seventeen".