1638000109 has 2 divisors, whose sum is σ = 1638000110. Its totient is φ = 1638000108.

The previous prime is 1638000107. The next prime is 1638000163. The reversal of 1638000109 is 9010008361.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1628526025 + 9474084 = 40355^2 + 3078^2 .

It is a cyclic number.

It is not a de Polignac number, because 1638000109 - 2¹ = 1638000107 is a prime.

Together with 1638000107, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1638000107) 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, 819000054 + 819000055.

It is an arithmetic number, because the mean of its divisors is an integer number (819000055).

Almost surely, 2^1638000109 is an apocalyptic number.

It is an amenable number.

1638000109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1638000109 is an equidigital number, since it uses as much as digits as its factorization.

1638000109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1638000109 is about 40472.2140362990. The cubic root of 1638000109 is about 1178.7941595836.

The spelling of 1638000109 in words is "one billion, six hundred thirty-eight million, one hundred nine", and thus it is an aban number.