21501443222047 has 2 divisors, whose sum is σ = 21501443222048. Its totient is φ = 21501443222046.

The previous prime is 21501443221991. The next prime is 21501443222087. The reversal of 21501443222047 is 74022234410512.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21501443222047 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21501443221997 and 21501443222015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21501443222087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750721611023 + 10750721611024.

It is an arithmetic number, because the mean of its divisors is an integer number (10750721611024).

Almost surely, 2^{21501443222047} is an apocalyptic number.

21501443222047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21501443222047 is an equidigital number, since it uses as much as digits as its factorization.

21501443222047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 107520, while the sum is 37.

Adding to 21501443222047 its reverse (74022234410512), we get a palindrome (95523677632559).

The spelling of 21501443222047 in words is "twenty-one trillion, five hundred one billion, four hundred forty-three million, two hundred twenty-two thousand, forty-seven".