8871993729 has 6 divisors (see below), whose sum is σ = 12815102066. Its totient is φ = 5914662480.

The previous prime is 8871993719. The next prime is 8871993743. The reversal of 8871993729 is 9273991788.

It can be written as a sum of positive squares in only one way, i.e., 8805945600 + 66048129 = 93840^2 + 8127^2 .

It is not a de Polignac number, because 8871993729 - 2¹³ = 8871985537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8871993719) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 492888532 + ... + 492888549.

Almost surely, 2^8871993729 is an apocalyptic number.

It is an amenable number.

8871993729 is a deficient number, since it is larger than the sum of its proper divisors (3943108337).

8871993729 is a wasteful number, since it uses less digits than its factorization.

8871993729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 985777087 (or 985777084 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 63.

The square root of 8871993729 is about 94191.2614258881. The cubic root of 8871993729 is about 2070.1750751593.

The spelling of 8871993729 in words is "eight billion, eight hundred seventy-one million, nine hundred ninety-three thousand, seven hundred twenty-nine".