66478680 has 96 divisors (see below), whose sum is σ = 220708800. Its totient is φ = 17346048.

The previous prime is 66478679. The next prime is 66478693. The reversal of 66478680 is 8687466.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14956 + ... + 18884.

It is an arithmetic number, because the mean of its divisors is an integer number (2299050).

Almost surely, 2^66478680 is an apocalyptic number.

66478680 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 66478680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110354400).

66478680 is an abundant number, since it is smaller than the sum of its proper divisors (154230120).

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

66478680 is a wasteful number, since it uses less digits than its factorization.

66478680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3993 (or 3986 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 66478680 is about 8153.4458972878. The cubic root of 66478680 is about 405.0986499515.

The spelling of 66478680 in words is "sixty-six million, four hundred seventy-eight thousand, six hundred eighty".