21655224301643 has 2 divisors, whose sum is σ = 21655224301644. Its totient is φ = 21655224301642.

The previous prime is 21655224301631. The next prime is 21655224301663. The reversal of 21655224301643 is 34610342255612.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21655224301643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21655224301594 and 21655224301603.

It is not a weakly prime, because it can be changed into another prime (21655224301663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10827612150821 + 10827612150822.

It is an arithmetic number, because the mean of its divisors is an integer number (10827612150822).

Almost surely, 2^{21655224301643} is an apocalyptic number.

21655224301643 is a deficient number, since it is larger than the sum of its proper divisors (1).

21655224301643 is an equidigital number, since it uses as much as digits as its factorization.

21655224301643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1036800, while the sum is 44.

The spelling of 21655224301643 in words is "twenty-one trillion, six hundred fifty-five billion, two hundred twenty-four million, three hundred one thousand, six hundred forty-three".