221407 has 8 divisors (see below), whose sum is σ = 239360. Its totient is φ = 204120.

The previous prime is 221401. The next prime is 221411. The reversal of 221407 is 704122.

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 221407 - 2³ = 221399 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 (221401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 682 + ... + 952.

It is an arithmetic number, because the mean of its divisors is an integer number (29920).

2²²¹⁴⁰⁷ is an apocalyptic number.

221407 is a deficient number, since it is larger than the sum of its proper divisors (17953).

221407 is a wasteful number, since it uses less digits than its factorization.

221407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333.

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 221407 is about 470.5390525769. The cubic root of 221407 is about 60.4965278157.

Adding to 221407 its reverse (704122), we get a palindrome (925529).

The spelling of 221407 in words is "two hundred twenty-one thousand, four hundred seven", and thus it is an iban number.