221207 has 4 divisors (see below), whose sum is σ = 252816. Its totient is φ = 189600.
The previous prime is 221203. The next prime is 221209. The reversal of 221207 is 702122.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 702122 = 2 ⋅351061.
It is a cyclic number.
It is not a de Polignac number, because 221207 - 22 = 221203 is a prime.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 221191 and 221200.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (221201) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15794 + ... + 15807.
It is an arithmetic number, because the mean of its divisors is an integer number (63204).
2221207 is an apocalyptic number.
221207 is a deficient number, since it is larger than the sum of its proper divisors (31609).
221207 is an equidigital number, since it uses as much as digits as its factorization.
221207 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 31608.
The product of its (nonzero) digits is 56, while the sum is 14.
The square root of 221207 is about 470.3264823503. The cubic root of 221207 is about 60.4783065451.
Adding to 221207 its reverse (702122), we get a palindrome (923329).
The spelling of 221207 in words is "two hundred twenty-one thousand, two hundred seven", and thus it is an iban number.
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