21066662328 has 32 divisors (see below), whose sum is σ = 54482749200. Its totient is φ = 6780075008.

The previous prime is 21066662291. The next prime is 21066662333. The reversal of 21066662328 is 82326666012.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21066662328.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 15133401 + ... + 15134792.

Almost surely, 2^21066662328 is an apocalyptic number.

It is an amenable number.

21066662328 is an abundant number, since it is smaller than the sum of its proper divisors (33416086872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21066662328 is a wasteful number, since it uses less digits than its factorization.

21066662328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30268231 (or 30268227 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 42.

The spelling of 21066662328 in words is "twenty-one billion, sixty-six million, six hundred sixty-two thousand, three hundred twenty-eight".