505291021 has 2 divisors, whose sum is σ = 505291022. Its totient is φ = 505291020.

The previous prime is 505291001. The next prime is 505291027. The reversal of 505291021 is 120192505.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 364275396 + 141015625 = 19086^2 + 11875^2 .

It is a cyclic number.

It is not a de Polignac number, because 505291021 - 2¹⁹ = 504766733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505291027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252645510 + 252645511.

It is an arithmetic number, because the mean of its divisors is an integer number (252645511).

Almost surely, 2^505291021 is an apocalyptic number.

It is an amenable number.

505291021 is a deficient number, since it is larger than the sum of its proper divisors (1).

505291021 is an equidigital number, since it uses as much as digits as its factorization.

505291021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 505291021 is about 22478.6792539064. The cubic root of 505291021 is about 796.4903657037.

The spelling of 505291021 in words is "five hundred five million, two hundred ninety-one thousand, twenty-one".