84072821 has 8 divisors (see below), whose sum is σ = 96141120. Its totient is φ = 72019008.

The previous prime is 84072811. The next prime is 84072841. The reversal of 84072821 is 12827048.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 84072821 - 2⁶ = 84072757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84072811) 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 7 ways as a sum of consecutive naturals, for example, 15725 + ... + 20381.

It is an arithmetic number, because the mean of its divisors is an integer number (12017640).

Almost surely, 2^84072821 is an apocalyptic number.

It is an amenable number.

84072821 is a deficient number, since it is larger than the sum of its proper divisors (12068299).

84072821 is a wasteful number, since it uses less digits than its factorization.

84072821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7243.

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 84072821 is about 9169.1232405285. The cubic root of 84072821 is about 438.0784333731.

Adding to 84072821 its reverse (12827048), we get a palindrome (96899869).

The spelling of 84072821 in words is "eighty-four million, seventy-two thousand, eight hundred twenty-one".