82920385681 has 27 divisors (see below), whose sum is σ = 99745508457. Its totient is φ = 68730054120.

The previous prime is 82920385663. The next prime is 82920385727. The reversal of 82920385681 is 18658302928.

The square root of 82920385681 is 287959.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 82920385681 - 2⁷ = 82920385553 is a prime.

It is a super-2 number, since 2×82920385681² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (82920385601) 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 in 26 ways as a sum of consecutive naturals, for example, 62486440 + ... + 62487766.

It is an arithmetic number, because the mean of its divisors is an integer number (3694278091).

Almost surely, 2^82920385681 is an apocalyptic number.

82920385681 is the 287959-th square number.

82920385681 is the 143980-th centered octagonal number.

It is an amenable number.

82920385681 is a deficient number, since it is larger than the sum of its proper divisors (16825122776).

82920385681 is an frugal number, since it uses more digits than its factorization.

82920385681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2730 (or 1365 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 52.

The spelling of 82920385681 in words is "eighty-two billion, nine hundred twenty million, three hundred eighty-five thousand, six hundred eighty-one".