505142221 has 4 divisors (see below), whose sum is σ = 507933244. Its totient is φ = 502351200.

The previous prime is 505142207. The next prime is 505142237. The reversal of 505142221 is 122241505.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122241505 = 5 ⋅24448301.

It can be written as a sum of positive squares in 2 ways, for example, as 77686596 + 427455625 = 8814^2 + 20675^2 .

It is a cyclic number.

It is not a de Polignac number, because 505142221 - 2¹¹ = 505140173 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 505142192 and 505142201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505142291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1395240 + ... + 1395601.

It is an arithmetic number, because the mean of its divisors is an integer number (126983311).

Almost surely, 2^505142221 is an apocalyptic number.

It is an amenable number.

505142221 is a deficient number, since it is larger than the sum of its proper divisors (2791023).

505142221 is a wasteful number, since it uses less digits than its factorization.

505142221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2791022.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 505142221 is about 22475.3692072010. The cubic root of 505142221 is about 796.4121735351.

Adding to 505142221 its reverse (122241505), we get a palindrome (627383726).

The spelling of 505142221 in words is "five hundred five million, one hundred forty-two thousand, two hundred twenty-one".