6838921 has 2 divisors, whose sum is σ = 6838922. Its totient is φ = 6838920.

The previous prime is 6838919. The next prime is 6838927. The reversal of 6838921 is 1298386.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4243600 + 2595321 = 2060^2 + 1611^2 .

It is a cyclic number.

It is not a de Polignac number, because 6838921 - 2¹ = 6838919 is a prime.

Together with 6838919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6838927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3419460 + 3419461.

It is an arithmetic number, because the mean of its divisors is an integer number (3419461).

Almost surely, 2^6838921 is an apocalyptic number.

It is an amenable number.

6838921 is a deficient number, since it is larger than the sum of its proper divisors (1).

6838921 is an equidigital number, since it uses as much as digits as its factorization.

6838921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 6838921 is about 2615.1330750078. The cubic root of 6838921 is about 189.8144171285.

It can be divided in two parts, 683 and 8921, that added together give a square (9604 = 98²).

The spelling of 6838921 in words is "six million, eight hundred thirty-eight thousand, nine hundred twenty-one".