21001231241 has 2 divisors, whose sum is σ = 21001231242. Its totient is φ = 21001231240.

The previous prime is 21001231213. The next prime is 21001231267. The reversal of 21001231241 is 14213210012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16239679225 + 4761552016 = 127435^2 + 69004^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001231241 is a prime.

It is not a weakly prime, because it can be changed into another prime (21001231211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500615620 + 10500615621.

It is an arithmetic number, because the mean of its divisors is an integer number (10500615621).

Almost surely, 2^21001231241 is an apocalyptic number.

It is an amenable number.

21001231241 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001231241 is an equidigital number, since it uses as much as digits as its factorization.

21001231241 is an evil number, because the sum of its binary digits is even.

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

Adding to 21001231241 its reverse (14213210012), we get a palindrome (35214441253).

The spelling of 21001231241 in words is "twenty-one billion, one million, two hundred thirty-one thousand, two hundred forty-one".