66578880 has 112 divisors (see below), whose sum is σ = 213018624. Its totient is φ = 17617920.

The previous prime is 66578857. The next prime is 66578881. The reversal of 66578880 is 8887566.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66578881) 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, 213925 + ... + 214235.

It is an arithmetic number, because the mean of its divisors is an integer number (1901952).

Almost surely, 2^66578880 is an apocalyptic number.

66578880 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 66578880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106509312).

66578880 is an abundant number, since it is smaller than the sum of its proper divisors (146439744).

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

66578880 is a wasteful number, since it uses less digits than its factorization.

66578880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554 (or 544 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 48.

The square root of 66578880 is about 8159.5882249045. The cubic root of 66578880 is about 405.3020761138.

The spelling of 66578880 in words is "sixty-six million, five hundred seventy-eight thousand, eight hundred eighty".