9916559881 has 4 divisors (see below), whose sum is σ = 9933988500. Its totient is φ = 9899131264.

The previous prime is 9916559839. The next prime is 9916559927. The reversal of 9916559881 is 1889556199.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 891559881 + 9025000000 = 29859^2 + 95000^2 .

It is a cyclic number.

It is not a de Polignac number, because 9916559881 - 2¹⁹ = 9916035593 is a prime.

It is a super-2 number, since 2×9916559881² (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 (9916550881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8713456 + ... + 8714593.

It is an arithmetic number, because the mean of its divisors is an integer number (2483497125).

Almost surely, 2^9916559881 is an apocalyptic number.

It is an amenable number.

9916559881 is a deficient number, since it is larger than the sum of its proper divisors (17428619).

9916559881 is a wasteful number, since it uses less digits than its factorization.

9916559881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17428618.

The product of its digits is 6998400, while the sum is 61.

The square root of 9916559881 is about 99581.9254734513. The cubic root of 9916559881 is about 2148.4257364218.

The spelling of 9916559881 in words is "nine billion, nine hundred sixteen million, five hundred fifty-nine thousand, eight hundred eighty-one".