66004920 has 144 divisors (see below), whose sum is σ = 221817960. Its totient is φ = 17019264.

The previous prime is 66004901. The next prime is 66004949. The reversal of 66004920 is 2940066.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 795199 + ... + 795281.

Almost surely, 2^66004920 is an apocalyptic number.

66004920 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 66004920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110908980).

66004920 is an abundant number, since it is smaller than the sum of its proper divisors (155813040).

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

66004920 is a wasteful number, since it uses less digits than its factorization.

66004920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194 (or 140 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 66004920 is about 8124.3412040608. The cubic root of 66004920 is about 404.1340436818.

Adding to 66004920 its reverse (2940066), we get a palindrome (68944986).

The spelling of 66004920 in words is "sixty-six million, four thousand, nine hundred twenty".