245221 has 4 divisors (see below), whose sum is σ = 251244. Its totient is φ = 239200.

The previous prime is 245209. The next prime is 245251. The reversal of 245221 is 122542.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9025 + 236196 = 95^2 + 486^2 .

It is a cyclic number.

It is not a de Polignac number, because 245221 - 2¹⁵ = 212453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 245195 and 245204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2950 + ... + 3031.

It is an arithmetic number, because the mean of its divisors is an integer number (62811).

2²⁴⁵²²¹ is an apocalyptic number.

It is an amenable number.

245221 is a deficient number, since it is larger than the sum of its proper divisors (6023).

245221 is an equidigital number, since it uses as much as digits as its factorization.

245221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6022.

The product of its digits is 160, while the sum is 16.

The square root of 245221 is about 495.1979402219. The cubic root of 245221 is about 62.5920563435.

Adding to 245221 its reverse (122542), we get a palindrome (367763).

It can be divided in two parts, 245 and 221, that multiplied together give a palindrome (54145).

The spelling of 245221 in words is "two hundred forty-five thousand, two hundred twenty-one".