21789642966 has 64 divisors (see below), whose sum is σ = 56459020800. Its totient is φ = 5444257536.

The previous prime is 21789642937. The next prime is 21789642989. The reversal of 21789642966 is 66924698712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1039831 + ... + 1060578.

It is an arithmetic number, because the mean of its divisors is an integer number (882172200).

Almost surely, 2^21789642966 is an apocalyptic number.

21789642966 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21789642966 is an abundant number, since it is smaller than the sum of its proper divisors (34669377834).

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

21789642966 is a wasteful number, since it uses less digits than its factorization.

21789642966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100453.

The product of its digits is 15676416, while the sum is 60.

The spelling of 21789642966 in words is "twenty-one billion, seven hundred eighty-nine million, six hundred forty-two thousand, nine hundred sixty-six".