66135238400 has 432 divisors, whose sum is σ = 208900462848. Its totient is φ = 20127744000.

The previous prime is 66135238373. The next prime is 66135238409. The reversal of 66135238400 is 483253166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66135238409) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 21188840 + ... + 21191960.

Almost surely, 2^66135238400 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 66135238400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104450231424).

66135238400 is an abundant number, since it is smaller than the sum of its proper divisors (142765224448).

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

66135238400 is a wasteful number, since it uses less digits than its factorization.

66135238400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3208 (or 3189 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 38.

The spelling of 66135238400 in words is "sixty-six billion, one hundred thirty-five million, two hundred thirty-eight thousand, four hundred".