501101221 has 4 divisors (see below), whose sum is σ = 513323244. Its totient is φ = 488879200.

The previous prime is 501101213. The next prime is 501101257. The reversal of 501101221 is 122101105.

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 25250625 + 475850596 = 5025^2 + 21814^2 .

It is a cyclic number.

It is not a de Polignac number, because 501101221 - 2³ = 501101213 is a prime.

It is a super-2 number, since 2×501101221² = 502204867375381682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501101281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6110950 + ... + 6111031.

It is an arithmetic number, because the mean of its divisors is an integer number (128330811).

Almost surely, 2^501101221 is an apocalyptic number.

It is an amenable number.

501101221 is a deficient number, since it is larger than the sum of its proper divisors (12222023).

501101221 is a wasteful number, since it uses less digits than its factorization.

501101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12222022.

The product of its (nonzero) digits is 20, while the sum is 13.

The square root of 501101221 is about 22385.2902817900. The cubic root of 501101221 is about 794.2827918488.

Adding to 501101221 its reverse (122101105), we get a palindrome (623202326).

The spelling of 501101221 in words is "five hundred one million, one hundred one thousand, two hundred twenty-one".