21789779200 has 108 divisors (see below), whose sum is σ = 61637964640. Its totient is φ = 7470766080.

The previous prime is 21789779197. The next prime is 21789779233. The reversal of 21789779200 is 297798712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 198390 + ... + 287989.

Almost surely, 2^21789779200 is an apocalyptic number.

21789779200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21789779200 is an abundant number, since it is smaller than the sum of its proper divisors (39848185440).

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

21789779200 is an equidigital number, since it uses as much as digits as its factorization.

21789779200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486412 (or 486393 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 52.

The spelling of 21789779200 in words is "twenty-one billion, seven hundred eighty-nine million, seven hundred seventy-nine thousand, two hundred".