21533643056 has 40 divisors (see below), whose sum is σ = 42685419744. Its totient is φ = 10519741440.

The previous prime is 21533643023. The next prime is 21533643127. The reversal of 21533643056 is 65034633512.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151685 + ... + 257051.

Almost surely, 2^21533643056 is an apocalyptic number.

It is an amenable number.

21533643056 is a deficient number, since it is larger than the sum of its proper divisors (21151776688).

21533643056 is a wasteful number, since it uses less digits than its factorization.

21533643056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105669 (or 105663 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 38.

The spelling of 21533643056 in words is "twenty-one billion, five hundred thirty-three million, six hundred forty-three thousand, fifty-six".