21242422247 has 2 divisors, whose sum is σ = 21242422248. Its totient is φ = 21242422246.

The previous prime is 21242422177. The next prime is 21242422261. The reversal of 21242422247 is 74222424212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21242422247 - 2¹⁸ = 21242160103 is a prime.

It is a super-3 number, since 3×21242422247³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21242422297) 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, 10621211123 + 10621211124.

It is an arithmetic number, because the mean of its divisors is an integer number (10621211124).

Almost surely, 2^21242422247 is an apocalyptic number.

21242422247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21242422247 is an equidigital number, since it uses as much as digits as its factorization.

21242422247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28672, while the sum is 32.

Adding to 21242422247 its reverse (74222424212), we get a palindrome (95464846459).

The spelling of 21242422247 in words is "twenty-one billion, two hundred forty-two million, four hundred twenty-two thousand, two hundred forty-seven".