521453221 has 2 divisors, whose sum is σ = 521453222. Its totient is φ = 521453220.

The previous prime is 521453213. The next prime is 521453249. The reversal of 521453221 is 122354125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 449016100 + 72437121 = 21190^2 + 8511^2 .

It is a cyclic number.

It is not a de Polignac number, because 521453221 - 2³ = 521453213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521453021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260726610 + 260726611.

It is an arithmetic number, because the mean of its divisors is an integer number (260726611).

Almost surely, 2^521453221 is an apocalyptic number.

It is an amenable number.

521453221 is a deficient number, since it is larger than the sum of its proper divisors (1).

521453221 is an equidigital number, since it uses as much as digits as its factorization.

521453221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2400, while the sum is 25.

The square root of 521453221 is about 22835.3502491203. The cubic root of 521453221 is about 804.8935579334.

The spelling of 521453221 in words is "five hundred twenty-one million, four hundred fifty-three thousand, two hundred twenty-one".