643436248 has 96 divisors (see below), whose sum is σ = 1560504960. Its totient is φ = 246274560.

The previous prime is 643436243. The next prime is 643436303. The reversal of 643436248 is 842634346.

It is a self number, because there is not a number n which added to its sum of digits gives 643436248.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643436243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 155940 + ... + 160012.

It is an arithmetic number, because the mean of its divisors is an integer number (16255260).

Almost surely, 2^643436248 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 643436248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (780252480).

643436248 is an abundant number, since it is smaller than the sum of its proper divisors (917068712).

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

643436248 is a wasteful number, since it uses less digits than its factorization.

643436248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4137 (or 4126 counting only the distinct ones).

The product of its digits is 331776, while the sum is 40.

The square root of 643436248 is about 25366.0451785453. The cubic root of 643436248 is about 863.3134513723.

The spelling of 643436248 in words is "six hundred forty-three million, four hundred thirty-six thousand, two hundred forty-eight".