821217263 has 2 divisors, whose sum is σ = 821217264. Its totient is φ = 821217262.

The previous prime is 821217233. The next prime is 821217269. The reversal of 821217263 is 362712128.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 821217263 - 2¹⁰ = 821216239 is a prime.

It is a super-2 number, since 2×821217263² = 1348795586098422338, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821217269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410608631 + 410608632.

It is an arithmetic number, because the mean of its divisors is an integer number (410608632).

Almost surely, 2^821217263 is an apocalyptic number.

821217263 is a deficient number, since it is larger than the sum of its proper divisors (1).

821217263 is an equidigital number, since it uses as much as digits as its factorization.

821217263 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 32.

The square root of 821217263 is about 28656.8885784902. Note that the first 3 decimals coincide. The cubic root of 821217263 is about 936.4530821854.

The spelling of 821217263 in words is "eight hundred twenty-one million, two hundred seventeen thousand, two hundred sixty-three".