82856623721 has 2 divisors, whose sum is σ = 82856623722. Its totient is φ = 82856623720.

The previous prime is 82856623679. The next prime is 82856623793. The reversal of 82856623721 is 12732665828.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73299606121 + 9557017600 = 270739^2 + 97760^2 .

It is a cyclic number.

It is not a de Polignac number, because 82856623721 - 2²² = 82852429417 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 82856623721.

It is not a weakly prime, because it can be changed into another prime (82856623921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41428311860 + 41428311861.

It is an arithmetic number, because the mean of its divisors is an integer number (41428311861).

Almost surely, 2^82856623721 is an apocalyptic number.

It is an amenable number.

82856623721 is a deficient number, since it is larger than the sum of its proper divisors (1).

82856623721 is an equidigital number, since it uses as much as digits as its factorization.

82856623721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1935360, while the sum is 50.

The spelling of 82856623721 in words is "eighty-two billion, eight hundred fifty-six million, six hundred twenty-three thousand, seven hundred twenty-one".