820471087 has 2 divisors, whose sum is σ = 820471088. Its totient is φ = 820471086.

The previous prime is 820471073. The next prime is 820471133. The reversal of 820471087 is 780174028.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820471087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820471007) 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, 410235543 + 410235544.

It is an arithmetic number, because the mean of its divisors is an integer number (410235544).

Almost surely, 2^820471087 is an apocalyptic number.

820471087 is a deficient number, since it is larger than the sum of its proper divisors (1).

820471087 is an equidigital number, since it uses as much as digits as its factorization.

820471087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 820471087 is about 28643.8664813255. The cubic root of 820471087 is about 936.1693689753.

The spelling of 820471087 in words is "eight hundred twenty million, four hundred seventy-one thousand, eighty-seven".