8279421921 has 6 divisors (see below), whose sum is σ = 11959165010. Its totient is φ = 5519614608.

The previous prime is 8279421877. The next prime is 8279421979. The reversal of 8279421921 is 1291249728.

It can be written as a sum of positive squares in only one way, i.e., 6362295696 + 1917126225 = 79764^2 + 43785^2 .

It is not a de Polignac number, because 8279421921 - 2¹⁷ = 8279290849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8279421721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 459967876 + ... + 459967893.

Almost surely, 2^8279421921 is an apocalyptic number.

It is an amenable number.

8279421921 is a deficient number, since it is larger than the sum of its proper divisors (3679743089).

8279421921 is a wasteful number, since it uses less digits than its factorization.

8279421921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919935775 (or 919935772 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 8279421921 is about 90991.3288231357. The cubic root of 8279421921 is about 2023.0192017994.

The spelling of 8279421921 in words is "eight billion, two hundred seventy-nine million, four hundred twenty-one thousand, nine hundred twenty-one".