3809799821 has 2 divisors, whose sum is σ = 3809799822. Its totient is φ = 3809799820.

The previous prime is 3809799817. The next prime is 3809799869. The reversal of 3809799821 is 1289979083.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3397141225 + 412658596 = 58285^2 + 20314^2 .

It is a cyclic number.

It is not a de Polignac number, because 3809799821 - 2² = 3809799817 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3809799881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1904899910 + 1904899911.

It is an arithmetic number, because the mean of its divisors is an integer number (1904899911).

Almost surely, 2^3809799821 is an apocalyptic number.

It is an amenable number.

3809799821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3809799821 is an equidigital number, since it uses as much as digits as its factorization.

3809799821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1959552, while the sum is 56.

The square root of 3809799821 is about 61723.5758928466. The cubic root of 3809799821 is about 1561.8310492045.

The spelling of 3809799821 in words is "three billion, eight hundred nine million, seven hundred ninety-nine thousand, eight hundred twenty-one".