8391729819 has 24 divisors (see below), whose sum is σ = 12467136976. Its totient is φ = 5016211200.

The previous prime is 8391729803. The next prime is 8391729847. The reversal of 8391729819 is 9189271938.

It is not a de Polignac number, because 8391729819 - 2⁴ = 8391729803 is a prime.

It is a super-2 number, since 2×8391729819² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8391729869) 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 23 ways as a sum of consecutive naturals, for example, 131842 + ... + 184839.

Almost surely, 2^8391729819 is an apocalyptic number.

8391729819 is a deficient number, since it is larger than the sum of its proper divisors (4075407157).

8391729819 is a wasteful number, since it uses less digits than its factorization.

8391729819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316779 (or 316768 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 57.

The square root of 8391729819 is about 91606.3852523393. The cubic root of 8391729819 is about 2032.1253690287.

The spelling of 8391729819 in words is "eight billion, three hundred ninety-one million, seven hundred twenty-nine thousand, eight hundred nineteen".