643064652 has 72 divisors (see below), whose sum is σ = 1717148160. Its totient is φ = 202353120.

The previous prime is 643064533. The next prime is 643064663. The reversal of 643064652 is 256460346.

643064652 is a `hidden beast` number, since 6 + 4 + 3 + 0 + 646 + 5 + 2 = 666.

It is a super-2 number, since 2×643064652² = 827064293303762208, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 211213 + ... + 214235.

It is an arithmetic number, because the mean of its divisors is an integer number (23849280).

Almost surely, 2^643064652 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 643064652, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (858574080).

643064652 is an abundant number, since it is smaller than the sum of its proper divisors (1074083508).

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

643064652 is a wasteful number, since it uses less digits than its factorization.

643064652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3363 (or 3358 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 643064652 is about 25358.7194471645. The cubic root of 643064652 is about 863.1472263564.

The spelling of 643064652 in words is "six hundred forty-three million, sixty-four thousand, six hundred fifty-two".