6821947 has 12 divisors (see below), whose sum is σ = 7921368. Its totient is φ = 5806400.

The previous prime is 6821933. The next prime is 6821959. The reversal of 6821947 is 7491286.

It is not a de Polignac number, because 6821947 - 2⁷ = 6821819 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6821747) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35622 + ... + 35812.

It is an arithmetic number, because the mean of its divisors is an integer number (660114).

Almost surely, 2^6821947 is an apocalyptic number.

6821947 is a deficient number, since it is larger than the sum of its proper divisors (1099421).

6821947 is a wasteful number, since it uses less digits than its factorization.

6821947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 219 counting only the distinct ones).

The product of its digits is 24192, while the sum is 37.

The square root of 6821947 is about 2611.8857172549. The cubic root of 6821947 is about 189.6572491016.

The spelling of 6821947 in words is "six million, eight hundred twenty-one thousand, nine hundred forty-seven".