66151171800 has 768 divisors, whose sum is σ = 278467891200. Its totient is φ = 14089420800.

The previous prime is 66151171789. The next prime is 66151171819. The reversal of 66151171800 is 817115166.

66151171800 is a `hidden beast` number, since 6 + 61 + 511 + 7 + 1 + 80 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 72613345 + ... + 72614255.

It is an arithmetic number, because the mean of its divisors is an integer number (362588400).

Almost surely, 2^66151171800 is an apocalyptic number.

66151171800 is a gapful number since it is divisible by the number (60) 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 66151171800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139233945600).

66151171800 is an abundant number, since it is smaller than the sum of its proper divisors (212316719400).

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

66151171800 is a wasteful number, since it uses less digits than its factorization.

66151171800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073 (or 1058 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 36.

Adding to 66151171800 its reverse (817115166), we get a palindrome (66968286966).

The spelling of 66151171800 in words is "sixty-six billion, one hundred fifty-one million, one hundred seventy-one thousand, eight hundred".