9836821 has 2 divisors, whose sum is σ = 9836822. Its totient is φ = 9836820.

The previous prime is 9836819. The next prime is 9836839. The reversal of 9836821 is 1286389.

9836821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7918596 + 1918225 = 2814^2 + 1385^2 .

It is a cyclic number.

It is not a de Polignac number, because 9836821 - 2¹ = 9836819 is a prime.

Together with 9836819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9836221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4918410 + 4918411.

It is an arithmetic number, because the mean of its divisors is an integer number (4918411).

Almost surely, 2^9836821 is an apocalyptic number.

It is an amenable number.

9836821 is a deficient number, since it is larger than the sum of its proper divisors (1).

9836821 is an equidigital number, since it uses as much as digits as its factorization.

9836821 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 9836821 is about 3136.3706732464. The cubic root of 9836821 is about 214.2651748144.

It can be divided in two parts, 98368 and 21, that added together give a palindrome (98389).

The spelling of 9836821 in words is "nine million, eight hundred thirty-six thousand, eight hundred twenty-one".