21655106672 has 10 divisors (see below), whose sum is σ = 41956769208. Its totient is φ = 10827553328.

The previous prime is 21655106663. The next prime is 21655106687. The reversal of 21655106672 is 27660155612.

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, 676722068 + ... + 676722099.

Almost surely, 2^21655106672 is an apocalyptic number.

It is an amenable number.

21655106672 is a deficient number, since it is larger than the sum of its proper divisors (20301662536).

21655106672 is a wasteful number, since it uses less digits than its factorization.

21655106672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1353444175 (or 1353444169 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 41.

The spelling of 21655106672 in words is "twenty-one billion, six hundred fifty-five million, one hundred six thousand, six hundred seventy-two".