8439707521 has 12 divisors (see below), whose sum is σ = 9978567060. Its totient is φ = 7115441760.

The previous prime is 8439707503. The next prime is 8439707537. The reversal of 8439707521 is 1257079348.

It can be written as a sum of positive squares in 2 ways, for example, as 2212761600 + 6226945921 = 47040^2 + 78911^2 .

It is not a de Polignac number, because 8439707521 - 2¹¹ = 8439705473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (8439707581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1408806 + ... + 1414783.

It is an arithmetic number, because the mean of its divisors is an integer number (831547255).

Almost surely, 2^8439707521 is an apocalyptic number.

It is an amenable number.

8439707521 is a deficient number, since it is larger than the sum of its proper divisors (1538859539).

8439707521 is a wasteful number, since it uses less digits than its factorization.

8439707521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2823664 (or 2823657 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 46.

The square root of 8439707521 is about 91867.8807908401. The cubic root of 8439707521 is about 2035.9907416725.

The spelling of 8439707521 in words is "eight billion, four hundred thirty-nine million, seven hundred seven thousand, five hundred twenty-one".