21444133397 has 2 divisors, whose sum is σ = 21444133398. Its totient is φ = 21444133396.

The previous prime is 21444133369. The next prime is 21444133441. The reversal of 21444133397 is 79333144412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19948455121 + 1495678276 = 141239^2 + 38674^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444133397 - 2¹⁰ = 21444132373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21444133367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722066698 + 10722066699.

It is an arithmetic number, because the mean of its divisors is an integer number (10722066699).

Almost surely, 2^21444133397 is an apocalyptic number.

It is an amenable number.

21444133397 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444133397 is an equidigital number, since it uses as much as digits as its factorization.

21444133397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 41.

The spelling of 21444133397 in words is "twenty-one billion, four hundred forty-four million, one hundred thirty-three thousand, three hundred ninety-seven".