21003203320349 has 2 divisors, whose sum is σ = 21003203320350. Its totient is φ = 21003203320348.

The previous prime is 21003203320303. The next prime is 21003203320381. The reversal of 21003203320349 is 94302330230012.

It is an a-pointer prime, because the next prime (21003203320381) can be obtained adding 21003203320349 to its sum of digits (32).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20979312981124 + 23890339225 = 4580318^2 + 154565^2 .

It is a cyclic number.

It is not a de Polignac number, because 21003203320349 - 2²⁰ = 21003202271773 is a prime.

It is a super-2 number, since 2×21003203320349² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21003203320399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501601660174 + 10501601660175.

It is an arithmetic number, because the mean of its divisors is an integer number (10501601660175).

Almost surely, 2^{21003203320349} is an apocalyptic number.

It is an amenable number.

21003203320349 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003203320349 is an equidigital number, since it uses as much as digits as its factorization.

21003203320349 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 32.

The spelling of 21003203320349 in words is "twenty-one trillion, three billion, two hundred three million, three hundred twenty thousand, three hundred forty-nine".