1665556984224 has 432 divisors, whose sum is σ = 5814944553600. Its totient is φ = 459452238336.

The previous prime is 1665556984129. The next prime is 1665556984229. The reversal of 1665556984224 is 4224896555661.

1665556984224 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 5 + 569 + 8 + 42 + 24 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (1665556984229) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 42600717 + ... + 42639795.

It is an arithmetic number, because the mean of its divisors is an integer number (13460519800).

Almost surely, 2^{1665556984224} is an apocalyptic number.

1665556984224 is a gapful number since it is divisible by the number (14) 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 1665556984224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2907472276800).

1665556984224 is an abundant number, since it is smaller than the sum of its proper divisors (4149387569376).

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

1665556984224 is an frugal number, since it uses more digits than its factorization.

1665556984224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39149 (or 39120 counting only the distinct ones).

The product of its digits is 124416000, while the sum is 63.

The spelling of 1665556984224 in words is "one trillion, six hundred sixty-five billion, five hundred fifty-six million, nine hundred eighty-four thousand, two hundred twenty-four".