820247 has 2 divisors, whose sum is σ = 820248. Its totient is φ = 820246.

The previous prime is 820243. The next prime is 820271. The reversal of 820247 is 742028.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 820247 - 2² = 820243 is a prime.

It is equal to p₆₅₄₃₅ and since 820247 and 65435 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 820247.

It is not a weakly prime, because it can be changed into another prime (820241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410123 + 410124.

It is an arithmetic number, because the mean of its divisors is an integer number (410124).

2⁸²⁰²⁴⁷ is an apocalyptic number.

820247 is a deficient number, since it is larger than the sum of its proper divisors (1).

820247 is an equidigital number, since it uses as much as digits as its factorization.

820247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 23.

The square root of 820247 is about 905.6748864797. The cubic root of 820247 is about 93.6084132380.

The spelling of 820247 in words is "eight hundred twenty thousand, two hundred forty-seven".