255305521 has 2 divisors, whose sum is σ = 255305522. Its totient is φ = 255305520.

The previous prime is 255305509. The next prime is 255305537. The reversal of 255305521 is 125503552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 225450225 + 29855296 = 15015^2 + 5464^2 .

It is a cyclic number.

It is not a de Polignac number, because 255305521 - 2¹⁷ = 255174449 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 255305521.

It is not a weakly prime, because it can be changed into another prime (255305581) 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, 127652760 + 127652761.

It is an arithmetic number, because the mean of its divisors is an integer number (127652761).

Almost surely, 2^255305521 is an apocalyptic number.

It is an amenable number.

255305521 is a deficient number, since it is larger than the sum of its proper divisors (1).

255305521 is an equidigital number, since it uses as much as digits as its factorization.

255305521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7500, while the sum is 28.

The square root of 255305521 is about 15978.2827925907. The cubic root of 255305521 is about 634.3857254320.

The spelling of 255305521 in words is "two hundred fifty-five million, three hundred five thousand, five hundred twenty-one".