21791836880 has 160 divisors (see below), whose sum is σ = 57863725056. Its totient is φ = 7560000000.

The previous prime is 21791836837. The next prime is 21791836907. The reversal of 21791836880 is 8863819712.

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, 1931255 + ... + 1942505.

Almost surely, 2^21791836880 is an apocalyptic number.

21791836880 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 21791836880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28931862528).

21791836880 is an abundant number, since it is smaller than the sum of its proper divisors (36071888176).

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

21791836880 is a wasteful number, since it uses less digits than its factorization.

21791836880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11377 (or 11371 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 53.

The spelling of 21791836880 in words is "twenty-one billion, seven hundred ninety-one million, eight hundred thirty-six thousand, eight hundred eighty".