8993671978 has 8 divisors (see below), whose sum is σ = 13675309668. Its totient is φ = 4435235424.

The previous prime is 8993671931. The next prime is 8993671987. The reversal of 8993671978 is 8791763998.

It can be written as a sum of positive squares in 2 ways, for example, as 8169809769 + 823862209 = 90387^2 + 28703^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×8993671978² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30800101 + ... + 30800392.

Almost surely, 2^8993671978 is an apocalyptic number.

8993671978 is a deficient number, since it is larger than the sum of its proper divisors (4681637690).

8993671978 is a wasteful number, since it uses less digits than its factorization.

8993671978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61600568.

The product of its digits is 41150592, while the sum is 67.

The square root of 8993671978 is about 94834.9723361588. The cubic root of 8993671978 is about 2079.5961970377.

The spelling of 8993671978 in words is "eight billion, nine hundred ninety-three million, six hundred seventy-one thousand, nine hundred seventy-eight".