505406240221 has 2 divisors, whose sum is σ = 505406240222. Its totient is φ = 505406240220.

The previous prime is 505406240201. The next prime is 505406240233. The reversal of 505406240221 is 122042604505.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 443036672100 + 62369568121 = 665610^2 + 249739^2 .

It is a cyclic number.

It is not a de Polignac number, because 505406240221 - 2¹⁷ = 505406109149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505406240201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252703120110 + 252703120111.

It is an arithmetic number, because the mean of its divisors is an integer number (252703120111).

Almost surely, 2^505406240221 is an apocalyptic number.

It is an amenable number.

505406240221 is a deficient number, since it is larger than the sum of its proper divisors (1).

505406240221 is an equidigital number, since it uses as much as digits as its factorization.

505406240221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 505406240221 its reverse (122042604505), we get a palindrome (627448844726).

The spelling of 505406240221 in words is "five hundred five billion, four hundred six million, two hundred forty thousand, two hundred twenty-one".