82821071 has 4 divisors (see below), whose sum is σ = 85677000. Its totient is φ = 79965144.

The previous prime is 82821041. The next prime is 82821113. The reversal of 82821071 is 17012828.

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

It is a cyclic number.

It is not a de Polignac number, because 82821071 - 2⁶ = 82821007 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 2855899 = 82821071 / (8 + 2 + 8 + 2 + 1 + 0 + 7 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82821001) 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, 1427921 + ... + 1427978.

It is an arithmetic number, because the mean of its divisors is an integer number (21419250).

Almost surely, 2^82821071 is an apocalyptic number.

82821071 is a deficient number, since it is larger than the sum of its proper divisors (2855929).

82821071 is a wasteful number, since it uses less digits than its factorization.

82821071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2855928.

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 82821071 is about 9100.6082763736. The cubic root of 82821071 is about 435.8933874361.

Adding to 82821071 its reverse (17012828), we get a palindrome (99833899).

The spelling of 82821071 in words is "eighty-two million, eight hundred twenty-one thousand, seventy-one".