501221 has 12 divisors (see below), whose sum is σ = 597132. Its totient is φ = 419328.

The previous prime is 501217. The next prime is 501223. The reversal of 501221 is 122105.

It can be written as a sum of positive squares in 2 ways, for example, as 240100 + 261121 = 490^2 + 511^2 .

It is not a de Polignac number, because 501221 - 2² = 501217 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 (501223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2501 + ... + 2693.

It is an arithmetic number, because the mean of its divisors is an integer number (49761).

2⁵⁰¹²²¹ is an apocalyptic number.

It is an amenable number.

501221 is a deficient number, since it is larger than the sum of its proper divisors (95911).

501221 is a wasteful number, since it uses less digits than its factorization.

501221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 501221 is about 707.9696321171. The cubic root of 501221 is about 79.4346073022.

Adding to 501221 its reverse (122105), we get a palindrome (623326).

The spelling of 501221 in words is "five hundred one thousand, two hundred twenty-one".