82117571 has 4 divisors (see below), whose sum is σ = 82135944. Its totient is φ = 82099200.

The previous prime is 82117561. The next prime is 82117583. The reversal of 82117571 is 17571128.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82117571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82117501) 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, 2336 + ... + 13026.

It is an arithmetic number, because the mean of its divisors is an integer number (20533986).

Almost surely, 2^82117571 is an apocalyptic number.

82117571 is a deficient number, since it is larger than the sum of its proper divisors (18373).

82117571 is a wasteful number, since it uses less digits than its factorization.

82117571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18372.

The product of its digits is 3920, while the sum is 32.

The square root of 82117571 is about 9061.8745853162. The cubic root of 82117571 is about 434.6556856123.

Adding to 82117571 its reverse (17571128), we get a palindrome (99688699).

The spelling of 82117571 in words is "eighty-two million, one hundred seventeen thousand, five hundred seventy-one".