550721 has 2 divisors, whose sum is σ = 550722. Its totient is φ = 550720.

The previous prime is 550717. The next prime is 550733. The reversal of 550721 is 127055.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 541696 + 9025 = 736^2 + 95^2 .

It is a cyclic number.

It is not a de Polignac number, because 550721 - 2² = 550717 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 550693 and 550702.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 550721.

It is not a weakly prime, because it can be changed into another prime (550621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275360 + 275361.

It is an arithmetic number, because the mean of its divisors is an integer number (275361).

2⁵⁵⁰⁷²¹ is an apocalyptic number.

It is an amenable number.

550721 is a deficient number, since it is larger than the sum of its proper divisors (1).

550721 is an equidigital number, since it uses as much as digits as its factorization.

550721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 550721 is about 742.1057876071. The cubic root of 550721 is about 81.9679132839.

Adding to 550721 its reverse (127055), we get a palindrome (677776).

The spelling of 550721 in words is "five hundred fifty thousand, seven hundred twenty-one".