21000012304849 has 2 divisors, whose sum is σ = 21000012304850. Its totient is φ = 21000012304848.

The previous prime is 21000012304757. The next prime is 21000012304853. The reversal of 21000012304849 is 94840321000012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20993028694225 + 6983610624 = 4581815^2 + 83568^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000012304849 is a prime.

It is not a weakly prime, because it can be changed into another prime (21000012304879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500006152424 + 10500006152425.

It is an arithmetic number, because the mean of its divisors is an integer number (10500006152425).

Almost surely, 2^{21000012304849} is an apocalyptic number.

It is an amenable number.

21000012304849 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000012304849 is an equidigital number, since it uses as much as digits as its factorization.

21000012304849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 21000012304849 in words is "twenty-one trillion, twelve million, three hundred four thousand, eight hundred forty-nine".