6777921 has 8 divisors (see below), whose sum is σ = 9172384. Its totient is φ = 4451040.

The previous prime is 6777839. The next prime is 6777923. The reversal of 6777921 is 1297776.

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

It is not a de Polignac number, because 6777921 - 2¹⁴ = 6761537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6777921.

It is not an unprimeable number, because it can be changed into a prime (6777923) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 16660 + ... + 17061.

It is an arithmetic number, because the mean of its divisors is an integer number (1146548).

Almost surely, 2^6777921 is an apocalyptic number.

It is an amenable number.

6777921 is a deficient number, since it is larger than the sum of its proper divisors (2394463).

6777921 is a wasteful number, since it uses less digits than its factorization.

6777921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33791.

The product of its digits is 37044, while the sum is 39.

The square root of 6777921 is about 2603.4440650799. Note that the first 3 decimals coincide. The cubic root of 6777921 is about 189.2483786879.

The spelling of 6777921 in words is "six million, seven hundred seventy-seven thousand, nine hundred twenty-one".