66811140 has 144 divisors (see below), whose sum is σ = 226751616. Its totient is φ = 15782400.

The previous prime is 66811109. The next prime is 66811183. The reversal of 66811140 is 4111866.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 80769 + ... + 81591.

It is an arithmetic number, because the mean of its divisors is an integer number (1574664).

Almost surely, 2^66811140 is an apocalyptic number.

66811140 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 66811140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113375808).

66811140 is an abundant number, since it is smaller than the sum of its proper divisors (159940476).

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

66811140 is a wasteful number, since it uses less digits than its factorization.

66811140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 890 (or 885 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 66811140 is about 8173.8081700025. The cubic root of 66811140 is about 405.7728270396.

The spelling of 66811140 in words is "sixty-six million, eight hundred eleven thousand, one hundred forty".