521057281 has 2 divisors, whose sum is σ = 521057282. Its totient is φ = 521057280.

The previous prime is 521057279. The next prime is 521057287. The reversal of 521057281 is 182750125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 483296256 + 37761025 = 21984^2 + 6145^2 .

It is a cyclic number.

It is not a de Polignac number, because 521057281 - 2¹ = 521057279 is a prime.

It is a super-2 number, since 2×521057281² = 543001380166225922, which contains 22 as substring.

Together with 521057279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (521057287) 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, 260528640 + 260528641.

It is an arithmetic number, because the mean of its divisors is an integer number (260528641).

Almost surely, 2^521057281 is an apocalyptic number.

It is an amenable number.

521057281 is a deficient number, since it is larger than the sum of its proper divisors (1).

521057281 is an equidigital number, since it uses as much as digits as its factorization.

521057281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5600, while the sum is 31.

The square root of 521057281 is about 22826.6791496266. The cubic root of 521057281 is about 804.6897874979.

The spelling of 521057281 in words is "five hundred twenty-one million, fifty-seven thousand, two hundred eighty-one".