8949965581 has 2 divisors, whose sum is σ = 8949965582. Its totient is φ = 8949965580.

The previous prime is 8949965569. The next prime is 8949965611. The reversal of 8949965581 is 1855699498.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7836675625 + 1113289956 = 88525^2 + 33366^2 .

It is a cyclic number.

It is not a de Polignac number, because 8949965581 - 2²⁵ = 8916411149 is a prime.

It is a super-3 number, since 3×8949965581³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8949960581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4474982790 + 4474982791.

It is an arithmetic number, because the mean of its divisors is an integer number (4474982791).

Almost surely, 2^8949965581 is an apocalyptic number.

It is an amenable number.

8949965581 is a deficient number, since it is larger than the sum of its proper divisors (1).

8949965581 is an equidigital number, since it uses as much as digits as its factorization.

8949965581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27993600, while the sum is 64.

The square root of 8949965581 is about 94604.2577318801. The cubic root of 8949965581 is about 2076.2219990127.

The spelling of 8949965581 in words is "eight billion, nine hundred forty-nine million, nine hundred sixty-five thousand, five hundred eighty-one".