66648704 has 64 divisors (see below), whose sum is σ = 142381800. Its totient is φ = 30965760.

The previous prime is 66648691. The next prime is 66648707. The reversal of 66648704 is 40784666.

It can be written as a sum of positive squares in 4 ways, for example, as 66455104 + 193600 = 8152^2 + 440^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66648707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 237044 + ... + 237324.

Almost surely, 2^66648704 is an apocalyptic number.

66648704 is a gapful number since it is divisible by the number (64) 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 66648704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71190900).

66648704 is an abundant number, since it is smaller than the sum of its proper divisors (75733096).

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

66648704 is a wasteful number, since it uses less digits than its factorization.

66648704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421 (or 409 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 41.

The square root of 66648704 is about 8163.8657509785. The cubic root of 66648704 is about 405.4437122446.

It can be divided in two parts, 6664 and 8704, that multiplied together give a square (58003456 = 7616²).

The spelling of 66648704 in words is "sixty-six million, six hundred forty-eight thousand, seven hundred four".