21142254443 has 2 divisors, whose sum is σ = 21142254444. Its totient is φ = 21142254442.

The previous prime is 21142254439. The next prime is 21142254449. The reversal of 21142254443 is 34445224112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21142254443 - 2² = 21142254439 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21142254449) 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, 10571127221 + 10571127222.

It is an arithmetic number, because the mean of its divisors is an integer number (10571127222).

Almost surely, 2^21142254443 is an apocalyptic number.

21142254443 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142254443 is an equidigital number, since it uses as much as digits as its factorization.

21142254443 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30720, while the sum is 32.

Adding to 21142254443 its reverse (34445224112), we get a palindrome (55587478555).

The spelling of 21142254443 in words is "twenty-one billion, one hundred forty-two million, two hundred fifty-four thousand, four hundred forty-three".