21795782112 has 144 divisors (see below), whose sum is σ = 66855952800. Its totient is φ = 6695709696.

The previous prime is 21795782101. The next prime is 21795782147. The reversal of 21795782112 is 21128759712.

21795782112 is a `hidden beast` number, since 2 + 1 + 79 + 578 + 2 + 1 + 1 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×21795782112² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2530389 + ... + 2538987.

It is an arithmetic number, because the mean of its divisors is an integer number (464277450).

Almost surely, 2^21795782112 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21795782112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33427976400).

21795782112 is an abundant number, since it is smaller than the sum of its proper divisors (45060170688).

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

21795782112 is a wasteful number, since it uses less digits than its factorization.

21795782112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9305 (or 9294 counting only the distinct ones).

The product of its digits is 141120, while the sum is 45.

The spelling of 21795782112 in words is "twenty-one billion, seven hundred ninety-five million, seven hundred eighty-two thousand, one hundred twelve".