1644164441 has 2 divisors, whose sum is σ = 1644164442. Its totient is φ = 1644164440.

The previous prime is 1644164437. The next prime is 1644164443. The reversal of 1644164441 is 1444614461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1552675216 + 91489225 = 39404^2 + 9565^2 .

It is a cyclic number.

It is not a de Polignac number, because 1644164441 - 2² = 1644164437 is a prime.

It is a super-3 number, since 3×1644164441³ (a number of 29 digits) contains 333 as substring.

Together with 1644164443, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1644164443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822082220 + 822082221.

It is an arithmetic number, because the mean of its divisors is an integer number (822082221).

Almost surely, 2^1644164441 is an apocalyptic number.

It is an amenable number.

1644164441 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644164441 is an equidigital number, since it uses as much as digits as its factorization.

1644164441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36864, while the sum is 35.

The square root of 1644164441 is about 40548.2976338095. The cubic root of 1644164441 is about 1180.2710382375.

The spelling of 1644164441 in words is "one billion, six hundred forty-four million, one hundred sixty-four thousand, four hundred forty-one".