21124241491 has 2 divisors, whose sum is σ = 21124241492. Its totient is φ = 21124241490.

The previous prime is 21124241471. The next prime is 21124241503. The reversal of 21124241491 is 19414242112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21124241491 - 2⁹ = 21124240979 is a prime.

It is not a weakly prime, because it can be changed into another prime (21124241461) 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, 10562120745 + 10562120746.

It is an arithmetic number, because the mean of its divisors is an integer number (10562120746).

Almost surely, 2^21124241491 is an apocalyptic number.

21124241491 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124241491 is an equidigital number, since it uses as much as digits as its factorization.

21124241491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4608, while the sum is 31.

The spelling of 21124241491 in words is "twenty-one billion, one hundred twenty-four million, two hundred forty-one thousand, four hundred ninety-one".