21155144022643 has 2 divisors, whose sum is σ = 21155144022644. Its totient is φ = 21155144022642.

The previous prime is 21155144022601. The next prime is 21155144022647. The reversal of 21155144022643 is 34622044155112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21155144022643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21155144022596 and 21155144022605.

It is not a weakly prime, because it can be changed into another prime (21155144022647) 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, 10577572011321 + 10577572011322.

It is an arithmetic number, because the mean of its divisors is an integer number (10577572011322).

Almost surely, 2^{21155144022643} is an apocalyptic number.

21155144022643 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155144022643 is an equidigital number, since it uses as much as digits as its factorization.

21155144022643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 230400, while the sum is 40.

Adding to 21155144022643 its reverse (34622044155112), we get a palindrome (55777188177755).

The spelling of 21155144022643 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-four million, twenty-two thousand, six hundred forty-three".