21956837760 has 1536 divisors, whose sum is σ = 99443635200. Its totient is φ = 4379443200.

The previous prime is 21956837743. The next prime is 21956837797. The reversal of 21956837760 is 6773865912.

21956837760 is a `hidden beast` number, since 2 + 1 + 9 + 568 + 3 + 7 + 76 + 0 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21956837697 and 21956837706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 359948130 + ... + 359948190.

It is an arithmetic number, because the mean of its divisors is an integer number (64741950).

Almost surely, 2^21956837760 is an apocalyptic number.

21956837760 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 21956837760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49721817600).

21956837760 is an abundant number, since it is smaller than the sum of its proper divisors (77486797440).

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

21956837760 is a wasteful number, since it uses less digits than its factorization.

21956837760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 137 counting only the distinct ones).

The product of its (nonzero) digits is 3810240, while the sum is 54.

The spelling of 21956837760 in words is "twenty-one billion, nine hundred fifty-six million, eight hundred thirty-seven thousand, seven hundred sixty".