66646528 has 160 divisors (see below), whose sum is σ = 164989440. Its totient is φ = 26542080.

The previous prime is 66646523. The next prime is 66646529. The reversal of 66646528 is 82564666.

It is not an unprimeable number, because it can be changed into a prime (66646523) 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, 2149873 + ... + 2149903.

It is an arithmetic number, because the mean of its divisors is an integer number (1031184).

Almost surely, 2^66646528 is an apocalyptic number.

66646528 is a gapful number since it is divisible by the number (68) 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 66646528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82494720).

66646528 is an abundant number, since it is smaller than the sum of its proper divisors (98342912).

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

66646528 is a wasteful number, since it uses less digits than its factorization.

66646528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 82 counting only the distinct ones).

The product of its digits is 414720, while the sum is 43.

The square root of 66646528 is about 8163.7324796933. The cubic root of 66646528 is about 405.4392997801.

The spelling of 66646528 in words is "sixty-six million, six hundred forty-six thousand, five hundred twenty-eight".