21003121241 has 2 divisors, whose sum is σ = 21003121242. Its totient is φ = 21003121240.

The previous prime is 21003121213. The next prime is 21003121273. The reversal of 21003121241 is 14212130012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12432250000 + 8570871241 = 111500^2 + 92579^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21003121241 is a prime.

It is a super-2 number, since 2×21003121241² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21003121141) 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, 10501560620 + 10501560621.

It is an arithmetic number, because the mean of its divisors is an integer number (10501560621).

Almost surely, 2^21003121241 is an apocalyptic number.

It is an amenable number.

21003121241 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003121241 is an equidigital number, since it uses as much as digits as its factorization.

21003121241 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21003121241 its reverse (14212130012), we get a palindrome (35215251253).

The spelling of 21003121241 in words is "twenty-one billion, three million, one hundred twenty-one thousand, two hundred forty-one".