66580380 has 120 divisors (see below), whose sum is σ = 212102352. Its totient is φ = 17480448.

The previous prime is 66580369. The next prime is 66580387. The reversal of 66580380 is 8308566.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66580387) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 117979 + ... + 118541.

Almost surely, 2^66580380 is an apocalyptic number.

66580380 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 66580380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106051176).

66580380 is an abundant number, since it is smaller than the sum of its proper divisors (145521972).

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

66580380 is a wasteful number, since it uses less digits than its factorization.

66580380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657 (or 646 counting only the distinct ones).

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

The square root of 66580380 is about 8159.6801407898. The cubic root of 66580380 is about 405.3051198646.

The spelling of 66580380 in words is "sixty-six million, five hundred eighty thousand, three hundred eighty".