6821971 has 8 divisors (see below), whose sum is σ = 7387520. Its totient is φ = 6262272.

The previous prime is 6821963. The next prime is 6822017. The reversal of 6821971 is 1791286.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 6821971 - 2³ = 6821963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6821911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1150 + ... + 3868.

It is an arithmetic number, because the mean of its divisors is an integer number (923440).

Almost surely, 2^6821971 is an apocalyptic number.

6821971 is a deficient number, since it is larger than the sum of its proper divisors (565549).

6821971 is a wasteful number, since it uses less digits than its factorization.

6821971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2925.

The product of its digits is 6048, while the sum is 34.

The square root of 6821971 is about 2611.8903116326. The cubic root of 6821971 is about 189.6574715097.

The spelling of 6821971 in words is "six million, eight hundred twenty-one thousand, nine hundred seventy-one".