646446528 has 224 divisors, whose sum is σ = 2339563520. Its totient is φ = 170449920.

The previous prime is 646446517. The next prime is 646446529. The reversal of 646446528 is 825644646.

646446528 is a `hidden beast` number, since 64 + 64 + 4 + 6 + 528 = 666.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-2 number, since 2×646446528² = 835786227126509568, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646446529) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 155193 + ... + 159303.

It is an arithmetic number, because the mean of its divisors is an integer number (10444480).

Almost surely, 2^646446528 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 646446528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1169781760).

646446528 is an abundant number, since it is smaller than the sum of its proper divisors (1693116992).

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

646446528 is a wasteful number, since it uses less digits than its factorization.

646446528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4152 (or 4136 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 45.

The square root of 646446528 is about 25425.3127414394. The cubic root of 646446528 is about 864.6576782595.

The spelling of 646446528 in words is "six hundred forty-six million, four hundred forty-six thousand, five hundred twenty-eight".