21142230443 has 4 divisors (see below), whose sum is σ = 21259038528. Its totient is φ = 21025422360.

The previous prime is 21142230427. The next prime is 21142230463. The reversal of 21142230443 is 34403224112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21142230443 - 2⁴ = 21142230427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21142230463) 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 in 3 ways as a sum of consecutive naturals, for example, 58403771 + ... + 58404132.

It is an arithmetic number, because the mean of its divisors is an integer number (5314759632).

Almost surely, 2^21142230443 is an apocalyptic number.

21142230443 is a deficient number, since it is larger than the sum of its proper divisors (116808085).

21142230443 is a wasteful number, since it uses less digits than its factorization.

21142230443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116808084.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21142230443 its reverse (34403224112), we get a palindrome (55545454555).

The spelling of 21142230443 in words is "twenty-one billion, one hundred forty-two million, two hundred thirty thousand, four hundred forty-three".