21422543644 has 6 divisors (see below), whose sum is σ = 37489451384. Its totient is φ = 10711271820.

The previous prime is 21422543609. The next prime is 21422543651. The reversal of 21422543644 is 44634522412.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2677817952 + ... + 2677817959.

Almost surely, 2^21422543644 is an apocalyptic number.

It is an amenable number.

21422543644 is a deficient number, since it is larger than the sum of its proper divisors (16066907740).

21422543644 is a wasteful number, since it uses less digits than its factorization.

21422543644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5355635915 (or 5355635913 counting only the distinct ones).

The product of its digits is 184320, while the sum is 37.

The spelling of 21422543644 in words is "twenty-one billion, four hundred twenty-two million, five hundred forty-three thousand, six hundred forty-four".