21066224447 has 2 divisors, whose sum is σ = 21066224448. Its totient is φ = 21066224446.

The previous prime is 21066224393. The next prime is 21066224513. The reversal of 21066224447 is 74442266012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21066224447 - 2⁶ = 21066224383 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21066224447.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21066274447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10533112223 + 10533112224.

It is an arithmetic number, because the mean of its divisors is an integer number (10533112224).

Almost surely, 2^21066224447 is an apocalyptic number.

21066224447 is a deficient number, since it is larger than the sum of its proper divisors (1).

21066224447 is an equidigital number, since it uses as much as digits as its factorization.

21066224447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129024, while the sum is 38.

The spelling of 21066224447 in words is "twenty-one billion, sixty-six million, two hundred twenty-four thousand, four hundred forty-seven".