104856821 has 2 divisors, whose sum is σ = 104856822. Its totient is φ = 104856820.

The previous prime is 104856811. The next prime is 104856823. The reversal of 104856821 is 128658401.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78127921 + 26728900 = 8839^2 + 5170^2 .

It is a cyclic number.

It is not a de Polignac number, because 104856821 - 2¹⁰ = 104855797 is a prime.

It is a Sophie Germain prime.

Together with 104856823, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is equal to p_6024968 and since 104856821 and 6024968 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (104856823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52428410 + 52428411.

It is an arithmetic number, because the mean of its divisors is an integer number (52428411).

Almost surely, 2^104856821 is an apocalyptic number.

It is an amenable number.

104856821 is a deficient number, since it is larger than the sum of its proper divisors (1).

104856821 is an equidigital number, since it uses as much as digits as its factorization.

104856821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 104856821 is about 10239.9619628200. The cubic root of 104856821 is about 471.5548640738.

The spelling of 104856821 in words is "one hundred four million, eight hundred fifty-six thousand, eight hundred twenty-one".