21444100220449 has 2 divisors, whose sum is σ = 21444100220450. Its totient is φ = 21444100220448.

The previous prime is 21444100220437. The next prime is 21444100220537. The reversal of 21444100220449 is 94402200144412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20747114010000 + 696986210449 = 4554900^2 + 834857^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444100220449 - 2⁹ = 21444100219937 is a prime.

It is not a weakly prime, because it can be changed into another prime (21444100220419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722050110224 + 10722050110225.

It is an arithmetic number, because the mean of its divisors is an integer number (10722050110225).

Almost surely, 2^{21444100220449} is an apocalyptic number.

It is an amenable number.

21444100220449 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444100220449 is an equidigital number, since it uses as much as digits as its factorization.

21444100220449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 73728, while the sum is 37.

The spelling of 21444100220449 in words is "twenty-one trillion, four hundred forty-four billion, one hundred million, two hundred twenty thousand, four hundred forty-nine".