1644406441 has 2 divisors, whose sum is σ = 1644406442. Its totient is φ = 1644406440.

The previous prime is 1644406417. The next prime is 1644406469. The reversal of 1644406441 is 1446044461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1445596441 + 198810000 = 38021^2 + 14100^2 .

It is a cyclic number.

It is not a de Polignac number, because 1644406441 - 2⁹ = 1644405929 is a prime.

It is a super-3 number, since 3×1644406441³ (a number of 29 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1644406397 and 1644406406.

It is not a weakly prime, because it can be changed into another prime (1644406411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822203220 + 822203221.

It is an arithmetic number, because the mean of its divisors is an integer number (822203221).

Almost surely, 2^1644406441 is an apocalyptic number.

It is an amenable number.

1644406441 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644406441 is an equidigital number, since it uses as much as digits as its factorization.

1644406441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36864, while the sum is 34.

The square root of 1644406441 is about 40551.2816196973. The cubic root of 1644406441 is about 1180.3289423359.

The spelling of 1644406441 in words is "one billion, six hundred forty-four million, four hundred six thousand, four hundred forty-one".