505666501 has 2 divisors, whose sum is σ = 505666502. Its totient is φ = 505666500.

The previous prime is 505666471. The next prime is 505666507. The reversal of 505666501 is 105666505.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 484044001 + 21622500 = 22001^2 + 4650^2 .

It is a cyclic number.

It is not a de Polignac number, because 505666501 - 2⁹ = 505665989 is a prime.

It is a super-2 number, since 2×505666501² = 511397220467166002, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505666507) 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, 252833250 + 252833251.

It is an arithmetic number, because the mean of its divisors is an integer number (252833251).

Almost surely, 2^505666501 is an apocalyptic number.

It is an amenable number.

505666501 is a deficient number, since it is larger than the sum of its proper divisors (1).

505666501 is an equidigital number, since it uses as much as digits as its factorization.

505666501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 34.

The square root of 505666501 is about 22487.0296170926. The cubic root of 505666501 is about 796.6876065954.

The spelling of 505666501 in words is "five hundred five million, six hundred sixty-six thousand, five hundred one".