83871021 has 16 divisors (see below), whose sum is σ = 120968960. Its totient is φ = 51382080.

The previous prime is 83871001. The next prime is 83871043. The reversal of 83871021 is 12017838.

It is a happy number.

It is not a de Polignac number, because 83871021 - 2⁷ = 83870893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 83871021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83871001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4236 + ... + 13626.

It is an arithmetic number, because the mean of its divisors is an integer number (7560560).

Almost surely, 2^83871021 is an apocalyptic number.

It is an amenable number.

83871021 is a deficient number, since it is larger than the sum of its proper divisors (37097939).

83871021 is a wasteful number, since it uses less digits than its factorization.

83871021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9636.

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 83871021 is about 9158.1123054918. The cubic root of 83871021 is about 437.7276459902.

Adding to 83871021 its reverse (12017838), we get a palindrome (95888859).

The spelling of 83871021 in words is "eighty-three million, eight hundred seventy-one thousand, twenty-one".