646021248 has 64 divisors (see below), whose sum is σ = 1722388320. Its totient is φ = 214538240.

The previous prime is 646021241. The next prime is 646021279. The reversal of 646021248 is 842120646.

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

It is not an unprimeable number, because it can be changed into a prime (646021241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104911 + ... + 110897.

Almost surely, 2^646021248 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 646021248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (861194160).

646021248 is an abundant number, since it is smaller than the sum of its proper divisors (1076367072).

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

646021248 is a wasteful number, since it uses less digits than its factorization.

646021248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6285 (or 6273 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 646021248 is about 25416.9480465299. The cubic root of 646021248 is about 864.4680248909.

The spelling of 646021248 in words is "six hundred forty-six million, twenty-one thousand, two hundred forty-eight".