21021301131247 has 2 divisors, whose sum is σ = 21021301131248. Its totient is φ = 21021301131246.

The previous prime is 21021301131203. The next prime is 21021301131283. The reversal of 21021301131247 is 74213110312012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21021301131247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21021301131947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510650565623 + 10510650565624.

It is an arithmetic number, because the mean of its divisors is an integer number (10510650565624).

Almost surely, 2^{21021301131247} is an apocalyptic number.

21021301131247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021301131247 is an equidigital number, since it uses as much as digits as its factorization.

21021301131247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 28.

Adding to 21021301131247 its reverse (74213110312012), we get a palindrome (95234411443259).

The spelling of 21021301131247 in words is "twenty-one trillion, twenty-one billion, three hundred one million, one hundred thirty-one thousand, two hundred forty-seven".