221382717 has 16 divisors (see below), whose sum is σ = 299476992. Its totient is φ = 145454400.

The previous prime is 221382713. The next prime is 221382731. The reversal of 221382717 is 717283122.

It is not a de Polignac number, because 221382717 - 2² = 221382713 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221382713) 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, 57967 + ... + 61667.

It is an arithmetic number, because the mean of its divisors is an integer number (18717312).

Almost surely, 2^221382717 is an apocalyptic number.

It is an amenable number.

221382717 is a deficient number, since it is larger than the sum of its proper divisors (78094275).

221382717 is a wasteful number, since it uses less digits than its factorization.

221382717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3988.

The product of its digits is 9408, while the sum is 33.

The square root of 221382717 is about 14878.9353449768. The cubic root of 221382717 is about 604.9431606552.

The spelling of 221382717 in words is "two hundred twenty-one million, three hundred eighty-two thousand, seven hundred seventeen".