1660821120 has 384 divisors, whose sum is σ = 6942723840. Its totient is φ = 357138432.

The previous prime is 1660821101. The next prime is 1660821133. The reversal of 1660821120 is 211280661.

1660821120 is a `hidden beast` number, since 16 + 608 + 21 + 1 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 684229 + ... + 686651.

It is an arithmetic number, because the mean of its divisors is an integer number (18080010).

Almost surely, 2^1660821120 is an apocalyptic number.

1660821120 is a gapful number since it is divisible by the number (10) 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 1660821120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3471361920).

1660821120 is an abundant number, since it is smaller than the sum of its proper divisors (5281902720).

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

1660821120 is a wasteful number, since it uses less digits than its factorization.

1660821120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2472 (or 2457 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1660821120 is about 40753.1731279909. The cubic root of 1660821120 is about 1184.2433454047.

The spelling of 1660821120 in words is "one billion, six hundred sixty million, eight hundred twenty-one thousand, one hundred twenty".