82891217 has 4 divisors (see below), whose sum is σ = 84912996. Its totient is φ = 80869440.

The previous prime is 82891183. The next prime is 82891219. The reversal of 82891217 is 71219828.

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 32821441 + 50069776 = 5729^2 + 7076^2 .

It is a cyclic number.

It is not a de Polignac number, because 82891217 - 2⁶ = 82891153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82891219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1010828 + ... + 1010909.

It is an arithmetic number, because the mean of its divisors is an integer number (21228249).

Almost surely, 2^82891217 is an apocalyptic number.

It is an amenable number.

82891217 is a deficient number, since it is larger than the sum of its proper divisors (2021779).

82891217 is a wasteful number, since it uses less digits than its factorization.

82891217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2021778.

The product of its digits is 16128, while the sum is 38.

The square root of 82891217 is about 9104.4613789065. The cubic root of 82891217 is about 436.0164138954.

The spelling of 82891217 in words is "eighty-two million, eight hundred ninety-one thousand, two hundred seventeen".