82100020669 has 4 divisors (see below), whose sum is σ = 82101559644. Its totient is φ = 82098481696.

The previous prime is 82100020633. The next prime is 82100020679. The reversal of 82100020669 is 96602000128.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19330731225 + 62769289444 = 139035^2 + 250538^2 .

It is a cyclic number.

It is not a de Polignac number, because 82100020669 - 2³⁵ = 47740282301 is a prime.

It is a super-2 number, since 2×82100020669² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82100020679) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 686482 + ... + 797155.

It is an arithmetic number, because the mean of its divisors is an integer number (20525389911).

Almost surely, 2^82100020669 is an apocalyptic number.

It is an amenable number.

82100020669 is a deficient number, since it is larger than the sum of its proper divisors (1538975).

82100020669 is a wasteful number, since it uses less digits than its factorization.

82100020669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538974.

The product of its (nonzero) digits is 10368, while the sum is 34.

The spelling of 82100020669 in words is "eighty-two billion, one hundred million, twenty thousand, six hundred sixty-nine".