9945811816 has 16 divisors (see below), whose sum is σ = 19103236740. Its totient is φ = 4851615360.

The previous prime is 9945811793. The next prime is 9945811829. The reversal of 9945811816 is 6181185499.

It can be written as a sum of positive squares in 2 ways, for example, as 9854532900 + 91278916 = 99270^2 + 9554^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15160971 + ... + 15161626.

Almost surely, 2^9945811816 is an apocalyptic number.

It is an amenable number.

9945811816 is a deficient number, since it is larger than the sum of its proper divisors (9157424924).

9945811816 is a wasteful number, since it uses less digits than its factorization.

9945811816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30322644 (or 30322640 counting only the distinct ones).

The product of its digits is 622080, while the sum is 52.

The square root of 9945811816 is about 99728.6910372336. The cubic root of 9945811816 is about 2150.5361429096.

The spelling of 9945811816 in words is "nine billion, nine hundred forty-five million, eight hundred eleven thousand, eight hundred sixteen".