2111645221056 has 336 divisors, whose sum is σ = 7560487434240. Its totient is φ = 549519482880.

The previous prime is 2111645221051. The next prime is 2111645221069. The reversal of 2111645221056 is 6501225461112.

2111645221056 is a `hidden beast` number, since 2 + 1 + 1 + 1 + 645 + 2 + 2 + 1 + 0 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 2111645221056.

It is not an unprimeable number, because it can be changed into a prime (2111645221051) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1627975 + ... + 2621753.

Almost surely, 2^{2111645221056} 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 2111645221056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3780243717120).

2111645221056 is an abundant number, since it is smaller than the sum of its proper divisors (5448842213184).

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

2111645221056 is a wasteful number, since it uses less digits than its factorization.

2111645221056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993852 (or 993839 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 2111645221056 in words is "two trillion, one hundred eleven billion, six hundred forty-five million, two hundred twenty-one thousand, fifty-six".