221597 has 8 divisors (see below), whose sum is σ = 237600. Its totient is φ = 206064.

The previous prime is 221587. The next prime is 221603. The reversal of 221597 is 795122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221597 - 2⁴ = 221581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1979 + ... + 2087.

It is an arithmetic number, because the mean of its divisors is an integer number (29700).

2²²¹⁵⁹⁷ is an apocalyptic number.

It is an amenable number.

221597 is a deficient number, since it is larger than the sum of its proper divisors (16003).

221597 is a wasteful number, since it uses less digits than its factorization.

221597 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235.

The product of its digits is 1260, while the sum is 26.

The square root of 221597 is about 470.7409053821. The cubic root of 221597 is about 60.5138278617.

It can be divided in two parts, 221 and 597, that added together give a palindrome (818).

The spelling of 221597 in words is "two hundred twenty-one thousand, five hundred ninety-seven".