21909133933056 has 320 divisors, whose sum is σ = 65789655740160. Its totient is φ = 7287867260928.

The previous prime is 21909133933009. The next prime is 21909133933081. The reversal of 21909133933056 is 65033933190912.

21909133933056 is a `hidden beast` number, since 2 + 1 + 90 + 91 + 3 + 393 + 30 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 21909133932993 and 21909133933011.

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, 545295240 + ... + 545335416.

It is an arithmetic number, because the mean of its divisors is an integer number (205592674188).

Almost surely, 2^{21909133933056} 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 21909133933056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32894827870080).

21909133933056 is an abundant number, since it is smaller than the sum of its proper divisors (43880521807104).

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

21909133933056 is an frugal number, since it uses more digits than its factorization.

21909133933056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40703 (or 40669 counting only the distinct ones).

The product of its (nonzero) digits is 3542940, while the sum is 54.

The spelling of 21909133933056 in words is "twenty-one trillion, nine hundred nine billion, one hundred thirty-three million, nine hundred thirty-three thousand, fifty-six".