2121605568 has 224 divisors, whose sum is σ = 6449080320. Its totient is φ = 683596800.

The previous prime is 2121605501. The next prime is 2121605581. The reversal of 2121605568 is 8655061212.

2121605568 is a `hidden beast` number, since 21 + 21 + 60 + 556 + 8 = 666.

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

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, 12263530 + ... + 12263702.

Almost surely, 2^2121605568 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 2121605568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3224540160).

2121605568 is an abundant number, since it is smaller than the sum of its proper divisors (4327474752).

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

2121605568 is a wasteful number, since it uses less digits than its factorization.

2121605568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 376 counting only the distinct ones).

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

The square root of 2121605568 is about 46060.8897873239. The cubic root of 2121605568 is about 1284.9558783117.

The spelling of 2121605568 in words is "two billion, one hundred twenty-one million, six hundred five thousand, five hundred sixty-eight".