21066696880 has 160 divisors (see below), whose sum is σ = 52285939200. Its totient is φ = 7871385600.

The previous prime is 21066696853. The next prime is 21066696883. The reversal of 21066696880 is 8869666012.

It is not an unprimeable number, because it can be changed into a prime (21066696883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 47987701 + ... + 47988139.

It is an arithmetic number, because the mean of its divisors is an integer number (326787120).

Almost surely, 2^21066696880 is an apocalyptic number.

21066696880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21066696880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26142969600).

21066696880 is an abundant number, since it is smaller than the sum of its proper divisors (31219242320).

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

21066696880 is a wasteful number, since it uses less digits than its factorization.

21066696880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 843 (or 837 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 52.

The spelling of 21066696880 in words is "twenty-one billion, sixty-six million, six hundred ninety-six thousand, eight hundred eighty".