18834821 has 2 divisors, whose sum is σ = 18834822. Its totient is φ = 18834820.

The previous prime is 18834811. The next prime is 18834841. The reversal of 18834821 is 12843881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17181025 + 1653796 = 4145^2 + 1286^2 .

It is a cyclic number.

It is not a de Polignac number, because 18834821 - 2¹⁰ = 18833797 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18834811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9417410 + 9417411.

It is an arithmetic number, because the mean of its divisors is an integer number (9417411).

Almost surely, 2^18834821 is an apocalyptic number.

It is an amenable number.

18834821 is a deficient number, since it is larger than the sum of its proper divisors (1).

18834821 is an equidigital number, since it uses as much as digits as its factorization.

18834821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12288, while the sum is 35.

The square root of 18834821 is about 4339.9102525283. The cubic root of 18834821 is about 266.0646431167.

The spelling of 18834821 in words is "eighteen million, eight hundred thirty-four thousand, eight hundred twenty-one".