2128205664 has 288 divisors, whose sum is σ = 6953899680. Its totient is φ = 636014592.

The previous prime is 2128205659. The next prime is 2128205753. The reversal of 2128205664 is 4665028212.

It is a happy number.

2128205664 is a `hidden beast` number, since 2 + 12 + 82 + 0 + 566 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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 pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3739972 + ... + 3740540.

It is an arithmetic number, because the mean of its divisors is an integer number (24145485).

Almost surely, 2^2128205664 is an apocalyptic number.

2128205664 is a gapful number since it is divisible by the number (24) 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 2128205664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3476949840).

2128205664 is an abundant number, since it is smaller than the sum of its proper divisors (4825694016).

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

2128205664 is a wasteful number, since it uses less digits than its factorization.

2128205664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 2128205664 is about 46132.4794911351. The cubic root of 2128205664 is about 1286.2869540335.

The spelling of 2128205664 in words is "two billion, one hundred twenty-eight million, two hundred five thousand, six hundred sixty-four".