66881700 has 180 divisors, whose sum is σ = 226860480. Its totient is φ = 17012160.

The previous prime is 66881699. The next prime is 66881719. The reversal of 66881700 is 718866.

66881700 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (180).

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

It is a zygodrome in base 3.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 186121 + ... + 186479.

It is an arithmetic number, because the mean of its divisors is an integer number (1260336).

Almost surely, 2^66881700 is an apocalyptic number.

66881700 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 66881700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113430240).

66881700 is an abundant number, since it is smaller than the sum of its proper divisors (159978780).

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

66881700 is a wasteful number, since it uses less digits than its factorization.

66881700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 408 (or 392 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 66881700 is about 8178.1232565913. The cubic root of 66881700 is about 405.9156238711.

The spelling of 66881700 in words is "sixty-six million, eight hundred eighty-one thousand, seven hundred".