66145680 has 160 divisors (see below), whose sum is σ = 230699520. Its totient is φ = 17418240.

The previous prime is 66145679. The next prime is 66145693. The reversal of 66145680 is 8654166.

66145680 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

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 31 ways as a sum of consecutive naturals, for example, 243945 + ... + 244215.

It is an arithmetic number, because the mean of its divisors is an integer number (1441872).

Almost surely, 2^66145680 is an apocalyptic number.

66145680 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 66145680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115349760).

66145680 is an abundant number, since it is smaller than the sum of its proper divisors (164553840).

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

66145680 is a wasteful number, since it uses less digits than its factorization.

66145680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406 (or 394 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 66145680 is about 8132.9994466986. Note that the first 3 decimals coincide. The cubic root of 66145680 is about 404.4211208580.

The spelling of 66145680 in words is "sixty-six million, one hundred forty-five thousand, six hundred eighty".