503303561 has 2 divisors, whose sum is σ = 503303562. Its totient is φ = 503303560.

The previous prime is 503303509. The next prime is 503303587. The reversal of 503303561 is 165303305.

It is an a-pointer prime, because the next prime (503303587) can be obtained adding 503303561 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 456463225 + 46840336 = 21365^2 + 6844^2 .

It is a cyclic number.

It is not a de Polignac number, because 503303561 - 2²⁶ = 436194697 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 503303561.

It is not a weakly prime, because it can be changed into another prime (503303761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 251651780 + 251651781.

It is an arithmetic number, because the mean of its divisors is an integer number (251651781).

Almost surely, 2^503303561 is an apocalyptic number.

It is an amenable number.

503303561 is a deficient number, since it is larger than the sum of its proper divisors (1).

503303561 is an equidigital number, since it uses as much as digits as its factorization.

503303561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4050, while the sum is 26.

The square root of 503303561 is about 22434.4280292590. The cubic root of 503303561 is about 795.4447156499. Note that the first 3 decimals are identical.

Adding to 503303561 its reverse (165303305), we get a palindrome (668606866).

The spelling of 503303561 in words is "five hundred three million, three hundred three thousand, five hundred sixty-one".