503405001221 has 2 divisors, whose sum is σ = 503405001222. Its totient is φ = 503405001220.

The previous prime is 503405001199. The next prime is 503405001247. The reversal of 503405001221 is 122100504305.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 503374641121 + 30360100 = 709489^2 + 5510^2 .

It is a cyclic number.

It is not a de Polignac number, because 503405001221 - 2¹⁸ = 503404739077 is a prime.

It is a super-3 number, since 3×503405001221³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (503405001721) 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 as a sum of consecutive naturals, namely, 251702500610 + 251702500611.

It is an arithmetic number, because the mean of its divisors is an integer number (251702500611).

Almost surely, 2^503405001221 is an apocalyptic number.

It is an amenable number.

503405001221 is a deficient number, since it is larger than the sum of its proper divisors (1).

503405001221 is an equidigital number, since it uses as much as digits as its factorization.

503405001221 is an odious number, because the sum of its binary digits is odd.

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

Adding to 503405001221 its reverse (122100504305), we get a palindrome (625505505526).

The spelling of 503405001221 in words is "five hundred three billion, four hundred five million, one thousand, two hundred twenty-one".