6991884085 has 4 divisors (see below), whose sum is σ = 8390260908. Its totient is φ = 5593507264.

The previous prime is 6991884071. The next prime is 6991884089. The reversal of 6991884085 is 5804881996.

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 1576248804 + 5415635281 = 39702^2 + 73591^2 .

It is a cyclic number.

It is not a de Polignac number, because 6991884085 - 2³¹ = 4844400437 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6991884089) 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, 699188404 + ... + 699188413.

It is an arithmetic number, because the mean of its divisors is an integer number (2097565227).

Almost surely, 2^6991884085 is an apocalyptic number.

It is an amenable number.

6991884085 is a deficient number, since it is larger than the sum of its proper divisors (1398376823).

6991884085 is a wasteful number, since it uses less digits than its factorization.

6991884085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1398376822.

The product of its (nonzero) digits is 4976640, while the sum is 58.

The square root of 6991884085 is about 83617.4867177913. The cubic root of 6991884085 is about 1912.1916022581.

The spelling of 6991884085 in words is "six billion, nine hundred ninety-one million, eight hundred eighty-four thousand, eighty-five".