66545040 has 80 divisors (see below), whose sum is σ = 207576000. Its totient is φ = 17634816.

The previous prime is 66545029. The next prime is 66545041. The reversal of 66545040 is 4054566.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 66544989 and 66545007.

It is not an unprimeable number, because it can be changed into a prime (66545041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42186 + ... + 43734.

It is an arithmetic number, because the mean of its divisors is an integer number (2594700).

Almost surely, 2^66545040 is an apocalyptic number.

66545040 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 66545040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103788000).

66545040 is an abundant number, since it is smaller than the sum of its proper divisors (141030960).

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

66545040 is a wasteful number, since it uses less digits than its factorization.

66545040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1744 (or 1738 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 66545040 is about 8157.5143272936. The cubic root of 66545040 is about 405.2333969440.

The spelling of 66545040 in words is "sixty-six million, five hundred forty-five thousand, forty".