505766531 has 2 divisors, whose sum is σ = 505766532. Its totient is φ = 505766530.

The previous prime is 505766509. The next prime is 505766533. The reversal of 505766531 is 135667505.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 505766531 - 2¹⁸ = 505504387 is a prime.

It is a super-2 number, since 2×505766531² = 511599567759547922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 505766533, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (505766533) 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, 252883265 + 252883266.

It is an arithmetic number, because the mean of its divisors is an integer number (252883266).

Almost surely, 2^505766531 is an apocalyptic number.

505766531 is the 10058-th centered decagonal number.

505766531 is a deficient number, since it is larger than the sum of its proper divisors (1).

505766531 is an equidigital number, since it uses as much as digits as its factorization.

505766531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 94500, while the sum is 38.

The square root of 505766531 is about 22489.2536781459. The cubic root of 505766531 is about 796.7401362151.

The spelling of 505766531 in words is "five hundred five million, seven hundred sixty-six thousand, five hundred thirty-one".