6891221986 has 16 divisors (see below), whose sum is σ = 11870048160. Its totient is φ = 2967511680.

The previous prime is 6891221977. The next prime is 6891221999.

6891221986 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8242671 + ... + 8243506.

It is an arithmetic number, because the mean of its divisors is an integer number (741878010).

Almost surely, 2^6891221986 is an apocalyptic number.

6891221986 is a deficient number, since it is larger than the sum of its proper divisors (4978826174).

6891221986 is a wasteful number, since it uses less digits than its factorization.

6891221986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16486209.

The product of its digits is 746496, while the sum is 52.

The square root of 6891221986 is about 83013.3843786651. The cubic root of 6891221986 is about 1902.9706057382.

The spelling of 6891221986 in words is "six billion, eight hundred ninety-one million, two hundred twenty-one thousand, nine hundred eighty-six".