66355520000 has 400 divisors, whose sum is σ = 206631006912. Its totient is φ = 20674560000.

The previous prime is 66355519999. The next prime is 66355520003. The reversal of 66355520000 is 2555366.

It is a tau number, because it is divible by the number of its divisors (400).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (66355520003) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 24638654 + ... + 24641346.

Almost surely, 2^66355520000 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 66355520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103315503456).

66355520000 is an abundant number, since it is smaller than the sum of its proper divisors (140275486912).

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

66355520000 is an equidigital number, since it uses as much as digits as its factorization.

66355520000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2749 (or 2718 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 32.

The spelling of 66355520000 in words is "sixty-six billion, three hundred fifty-five million, five hundred twenty thousand".