505623221 has 2 divisors, whose sum is σ = 505623222. Its totient is φ = 505623220.

The previous prime is 505623211. The next prime is 505623247. The reversal of 505623221 is 122326505.

It is an a-pointer prime, because the next prime (505623247) can be obtained adding 505623221 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 505620196 + 3025 = 22486^2 + 55^2 .

It is a cyclic number.

It is not a de Polignac number, because 505623221 - 2¹⁴ = 505606837 is a prime.

It is a super-2 number, since 2×505623221² = 511309683228829682, which contains 22 as substring.

It is equal to p_26636003 and since 505623221 and 26636003 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505623211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252811610 + 252811611.

It is an arithmetic number, because the mean of its divisors is an integer number (252811611).

Almost surely, 2^505623221 is an apocalyptic number.

It is an amenable number.

505623221 is a deficient number, since it is larger than the sum of its proper divisors (1).

505623221 is an equidigital number, since it uses as much as digits as its factorization.

505623221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 505623221 is about 22486.0672639748. The cubic root of 505623221 is about 796.6648764473.

Adding to 505623221 its reverse (122326505), we get a palindrome (627949726).

The spelling of 505623221 in words is "five hundred five million, six hundred twenty-three thousand, two hundred twenty-one".