505243121 has 4 divisors (see below), whose sum is σ = 510920100. Its totient is φ = 499566144.

The previous prime is 505243061. The next prime is 505243187. The reversal of 505243121 is 121342505.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 121342505 = 5 ⋅24268501.

It can be written as a sum of positive squares in 2 ways, for example, as 214915600 + 290327521 = 14660^2 + 17039^2 .

It is a cyclic number.

It is not a de Polignac number, because 505243121 - 2²² = 501048817 is a prime.

It is a super-2 number, since 2×505243121² = 510541222635641282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (505243021) 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, 2838356 + ... + 2838533.

It is an arithmetic number, because the mean of its divisors is an integer number (127730025).

Almost surely, 2^505243121 is an apocalyptic number.

It is an amenable number.

505243121 is a deficient number, since it is larger than the sum of its proper divisors (5676979).

505243121 is an equidigital number, since it uses as much as digits as its factorization.

505243121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5676978.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 505243121 is about 22477.6137745981. The cubic root of 505243121 is about 796.4651966476.

Adding to 505243121 its reverse (121342505), we get a palindrome (626585626).

The spelling of 505243121 in words is "five hundred five million, two hundred forty-three thousand, one hundred twenty-one".