6950221991 has 4 divisors (see below), whose sum is σ = 6953746632. Its totient is φ = 6946697352.

The previous prime is 6950221987. The next prime is 6950221997. The reversal of 6950221991 is 1991220596.

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

It is a cyclic number.

It is not a de Polignac number, because 6950221991 - 2² = 6950221987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6950221997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1759361 + ... + 1763306.

It is an arithmetic number, because the mean of its divisors is an integer number (1738436658).

Almost surely, 2^6950221991 is an apocalyptic number.

6950221991 is a deficient number, since it is larger than the sum of its proper divisors (3524641).

6950221991 is a wasteful number, since it uses less digits than its factorization.

6950221991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3524640.

The product of its (nonzero) digits is 87480, while the sum is 44.

The square root of 6950221991 is about 83367.9914055748. The cubic root of 6950221991 is about 1908.3860154476.

The spelling of 6950221991 in words is "six billion, nine hundred fifty million, two hundred twenty-one thousand, nine hundred ninety-one".