82689847021 has 2 divisors, whose sum is σ = 82689847022. Its totient is φ = 82689847020.

The previous prime is 82689847013. The next prime is 82689847049. The reversal of 82689847021 is 12074898628.

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., 46671121225 + 36018725796 = 216035^2 + 189786^2 .

It is a cyclic number.

It is not a de Polignac number, because 82689847021 - 2³ = 82689847013 is a prime.

It is a super-2 number, since 2×82689847021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82689847081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41344923510 + 41344923511.

It is an arithmetic number, because the mean of its divisors is an integer number (41344923511).

Almost surely, 2^82689847021 is an apocalyptic number.

It is an amenable number.

82689847021 is a deficient number, since it is larger than the sum of its proper divisors (1).

82689847021 is an equidigital number, since it uses as much as digits as its factorization.

82689847021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3096576, while the sum is 55.

The spelling of 82689847021 in words is "eighty-two billion, six hundred eighty-nine million, eight hundred forty-seven thousand, twenty-one".