1636844161 has 2 divisors, whose sum is σ = 1636844162. Its totient is φ = 1636844160.

The previous prime is 1636844159. The next prime is 1636844177. The reversal of 1636844161 is 1614486361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1356080625 + 280763536 = 36825^2 + 16756^2 .

It is a cyclic number.

It is not a de Polignac number, because 1636844161 - 2¹ = 1636844159 is a prime.

Together with 1636844159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1636844141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 818422080 + 818422081.

It is an arithmetic number, because the mean of its divisors is an integer number (818422081).

Almost surely, 2^1636844161 is an apocalyptic number.

It is an amenable number.

1636844161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1636844161 is an equidigital number, since it uses as much as digits as its factorization.

1636844161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82944, while the sum is 40.

The square root of 1636844161 is about 40457.9307552920. The cubic root of 1636844161 is about 1178.5167999327.

The spelling of 1636844161 in words is "one billion, six hundred thirty-six million, eight hundred forty-four thousand, one hundred sixty-one".