66798180 has 72 divisors (see below), whose sum is σ = 209174784. Its totient is φ = 17236800.

The previous prime is 66798161. The next prime is 66798181. The reversal of 66798180 is 8189766.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (66798181) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 406 + ... + 11565.

Almost surely, 2^66798180 is an apocalyptic number.

66798180 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 66798180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104587392).

66798180 is an abundant number, since it is smaller than the sum of its proper divisors (142376604).

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

66798180 is a wasteful number, since it uses less digits than its factorization.

66798180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12017 (or 12012 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 66798180 is about 8173.0153554242. The cubic root of 66798180 is about 405.7465881225.

The spelling of 66798180 in words is "sixty-six million, seven hundred ninety-eight thousand, one hundred eighty".