6448544021 has 2 divisors, whose sum is σ = 6448544022. Its totient is φ = 6448544020.

The previous prime is 6448544009. The next prime is 6448544059. The reversal of 6448544021 is 1204458446.

It is an a-pointer prime, because the next prime (6448544059) can be obtained adding 6448544021 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5965863121 + 482680900 = 77239^2 + 21970^2 .

It is a cyclic number.

It is not a de Polignac number, because 6448544021 - 2¹⁸ = 6448281877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6448544521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3224272010 + 3224272011.

It is an arithmetic number, because the mean of its divisors is an integer number (3224272011).

Almost surely, 2^6448544021 is an apocalyptic number.

It is an amenable number.

6448544021 is a deficient number, since it is larger than the sum of its proper divisors (1).

6448544021 is an equidigital number, since it uses as much as digits as its factorization.

6448544021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122880, while the sum is 38.

The square root of 6448544021 is about 80302.8269801257. The cubic root of 6448544021 is about 1861.3179102477.

The spelling of 6448544021 in words is "six billion, four hundred forty-eight million, five hundred forty-four thousand, twenty-one".