404148821 has 2 divisors, whose sum is σ = 404148822. Its totient is φ = 404148820.

The previous prime is 404148809. The next prime is 404148853. The reversal of 404148821 is 128841404.

It is an a-pointer prime, because the next prime (404148853) can be obtained adding 404148821 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 349166596 + 54982225 = 18686^2 + 7415^2 .

It is a cyclic number.

It is not a de Polignac number, because 404148821 - 2¹⁰ = 404147797 is a prime.

It is a Chen prime.

It is equal to p_21545672 and since 404148821 and 21545672 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 (404148881) 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, 202074410 + 202074411.

It is an arithmetic number, because the mean of its divisors is an integer number (202074411).

Almost surely, 2^404148821 is an apocalyptic number.

It is an amenable number.

404148821 is a deficient number, since it is larger than the sum of its proper divisors (1).

404148821 is an equidigital number, since it uses as much as digits as its factorization.

404148821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8192, while the sum is 32.

The square root of 404148821 is about 20103.4529621157. The cubic root of 404148821 is about 739.3449407556.

The spelling of 404148821 in words is "four hundred four million, one hundred forty-eight thousand, eight hundred twenty-one".