43072821 has 24 divisors (see below), whose sum is σ = 69323904. Its totient is φ = 25546560.

The previous prime is 43072817. The next prime is 43072831. The reversal of 43072821 is 12827034.

43072821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 43072821 - 2² = 43072817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43072831) 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 23 ways as a sum of consecutive naturals, for example, 25 + ... + 9281.

It is an arithmetic number, because the mean of its divisors is an integer number (2888496).

Almost surely, 2^43072821 is an apocalyptic number.

It is an amenable number.

43072821 is a deficient number, since it is larger than the sum of its proper divisors (26251083).

43072821 is a wasteful number, since it uses less digits than its factorization.

43072821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9321 (or 9318 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 43072821 is about 6562.9887246589. The cubic root of 43072821 is about 350.5374626811.

Adding to 43072821 its reverse (12827034), we get a palindrome (55899855).

The spelling of 43072821 in words is "forty-three million, seventy-two thousand, eight hundred twenty-one".