82195169809 has 3 divisors (see below), whose sum is σ = 82195456507. Its totient is φ = 82194883112.

The previous prime is 82195169807. The next prime is 82195169831. The reversal of 82195169809 is 90896159128.

The square root of 82195169809 is 286697.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 33056694225 + 49138475584 = 181815^2 + 221672^2 .

It is not a de Polignac number, because 82195169809 - 2¹ = 82195169807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82195169801) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 143349 + ... + 430045.

Almost surely, 2^82195169809 is an apocalyptic number.

82195169809 is the 286697-th square number.

82195169809 is the 143349-th centered octagonal number.

It is an amenable number.

82195169809 is a deficient number, since it is larger than the sum of its proper divisors (286698).

82195169809 is an frugal number, since it uses more digits than its factorization.

82195169809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573394 (or 286697 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 58.

It can be divided in two parts, 82195 and 169809, that added together give a square (252004 = 502²).

The spelling of 82195169809 in words is "eighty-two billion, one hundred ninety-five million, one hundred sixty-nine thousand, eight hundred nine".