8478071821 has 4 divisors (see below), whose sum is σ = 8534218144. Its totient is φ = 8421925500.

The previous prime is 8478071801. The next prime is 8478071843. The reversal of 8478071821 is 1281708748.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8478071821 - 2¹¹ = 8478069773 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 (8478071801) 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 3 ways as a sum of consecutive naturals, for example, 28072935 + ... + 28073236.

It is an arithmetic number, because the mean of its divisors is an integer number (2133554536).

Almost surely, 2^8478071821 is an apocalyptic number.

It is an amenable number.

8478071821 is a deficient number, since it is larger than the sum of its proper divisors (56146323).

8478071821 is a wasteful number, since it uses less digits than its factorization.

8478071821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56146322.

The product of its (nonzero) digits is 200704, while the sum is 46.

The square root of 8478071821 is about 92076.4455276158. The cubic root of 8478071821 is about 2039.0710736919.

The spelling of 8478071821 in words is "eight billion, four hundred seventy-eight million, seventy-one thousand, eight hundred twenty-one".