66773728 has 48 divisors (see below), whose sum is σ = 150885504. Its totient is φ = 28494720.

The previous prime is 66773719. The next prime is 66773731. The reversal of 66773728 is 82737766.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68283 + ... + 69253.

It is an arithmetic number, because the mean of its divisors is an integer number (3143448).

Almost surely, 2^66773728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66773728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75442752).

66773728 is an abundant number, since it is smaller than the sum of its proper divisors (84111776).

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

66773728 is a wasteful number, since it uses less digits than its factorization.

66773728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1295 (or 1287 counting only the distinct ones).

The product of its digits is 592704, while the sum is 46.

The square root of 66773728 is about 8171.5193201754. The cubic root of 66773728 is about 405.6970731686.

The spelling of 66773728 in words is "sixty-six million, seven hundred seventy-three thousand, seven hundred twenty-eight".