505321221221 has 2 divisors, whose sum is σ = 505321221222. Its totient is φ = 505321221220.

The previous prime is 505321221173. The next prime is 505321221233. The reversal of 505321221221 is 122122123505.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 325600336996 + 179720884225 = 570614^2 + 423935^2 .

It is a cyclic number.

It is not a de Polignac number, because 505321221221 - 2²² = 505317026917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505321241221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252660610610 + 252660610611.

It is an arithmetic number, because the mean of its divisors is an integer number (252660610611).

Almost surely, 2^505321221221 is an apocalyptic number.

It is an amenable number.

505321221221 is a deficient number, since it is larger than the sum of its proper divisors (1).

505321221221 is an equidigital number, since it uses as much as digits as its factorization.

505321221221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 505321221221 its reverse (122122123505), we get a palindrome (627443344726).

The spelling of 505321221221 in words is "five hundred five billion, three hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty-one".