82215857 has 2 divisors, whose sum is σ = 82215858. Its totient is φ = 82215856.

The previous prime is 82215839. The next prime is 82215943. The reversal of 82215857 is 75851228.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73119601 + 9096256 = 8551^2 + 3016^2 .

It is a cyclic number.

It is not a de Polignac number, because 82215857 - 2¹⁰ = 82214833 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 82215857.

It is not a weakly prime, because it can be changed into another prime (82215257) 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, 41107928 + 41107929.

It is an arithmetic number, because the mean of its divisors is an integer number (41107929).

Almost surely, 2^82215857 is an apocalyptic number.

It is an amenable number.

82215857 is a deficient number, since it is larger than the sum of its proper divisors (1).

82215857 is an equidigital number, since it uses as much as digits as its factorization.

82215857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 44800, while the sum is 38.

The square root of 82215857 is about 9067.2960136967. The cubic root of 82215857 is about 434.8290286842.

The spelling of 82215857 in words is "eighty-two million, two hundred fifteen thousand, eight hundred fifty-seven".