3638809 has 2 divisors, whose sum is σ = 3638810. Its totient is φ = 3638808.

The previous prime is 3638777. The next prime is 3638827. The reversal of 3638809 is 9088363.

It is a happy number.

3638809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3229209 + 409600 = 1797^2 + 640^2 .

It is a cyclic number.

It is not a de Polignac number, because 3638809 - 2⁵ = 3638777 is a prime.

It is not a weakly prime, because it can be changed into another prime (3638879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1819404 + 1819405.

It is an arithmetic number, because the mean of its divisors is an integer number (1819405).

Almost surely, 2^3638809 is an apocalyptic number.

It is an amenable number.

3638809 is a deficient number, since it is larger than the sum of its proper divisors (1).

3638809 is an equidigital number, since it uses as much as digits as its factorization.

3638809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 3638809 is about 1907.5662504878. The cubic root of 3638809 is about 153.8106544567.

It can be divided in two parts, 36 and 38809, that multiplied together give a square (1397124 = 1182²).

The spelling of 3638809 in words is "three million, six hundred thirty-eight thousand, eight hundred nine".