66791368800 has 1296 divisors, whose sum is σ = 281001389760. Its totient is φ = 15430072320.

The previous prime is 66791368783. The next prime is 66791368823. The reversal of 66791368800 is 886319766.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1296).

It is a super-2 number, since 2×66791368800² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 624218347 + ... + 624218453.

It is an arithmetic number, because the mean of its divisors is an integer number (216822060).

Almost surely, 2^66791368800 is an apocalyptic number.

66791368800 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 66791368800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140500694880).

66791368800 is an abundant number, since it is smaller than the sum of its proper divisors (214210020960).

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

66791368800 is a wasteful number, since it uses less digits than its factorization.

66791368800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 66791368800 in words is "sixty-six billion, seven hundred ninety-one million, three hundred sixty-eight thousand, eight hundred".