66155382400 has 96 divisors (see below), whose sum is σ = 165394101600. Its totient is φ = 26143226880.

The previous prime is 66155382361. The next prime is 66155382401. The reversal of 66155382400 is 428355166.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (66155382401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 141061 + ... + 390139.

It is an arithmetic number, because the mean of its divisors is an integer number (1722855225).

Almost surely, 2^66155382400 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 66155382400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82697050800).

66155382400 is an abundant number, since it is smaller than the sum of its proper divisors (99238719200).

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

66155382400 is a wasteful number, since it uses less digits than its factorization.

66155382400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249186 (or 249169 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 66155382400 in words is "sixty-six billion, one hundred fifty-five million, three hundred eighty-two thousand, four hundred".