1666543053600 has 360 divisors, whose sum is σ = 6218907433200. Its totient is φ = 434075604480.

The previous prime is 1666543053551. The next prime is 1666543053601. The reversal of 1666543053600 is 63503456661.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1666543053601) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 2487351 + ... + 3085449.

It is an arithmetic number, because the mean of its divisors is an integer number (17274742870).

Almost surely, 2^{1666543053600} is an apocalyptic number.

1666543053600 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 1666543053600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3109453716600).

1666543053600 is an abundant number, since it is smaller than the sum of its proper divisors (4552364379600).

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

1666543053600 is a wasteful number, since it uses less digits than its factorization.

1666543053600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 598174 (or 598152 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 45.

The spelling of 1666543053600 in words is "one trillion, six hundred sixty-six billion, five hundred forty-three million, fifty-three thousand, six hundred".