643257296 has 60 divisors (see below), whose sum is σ = 1401951936. Its totient is φ = 285552960.

The previous prime is 643257289. The next prime is 643257301. The reversal of 643257296 is 692752346.

643257296 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 79385 + ... + 87111.

Almost surely, 2^643257296 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 643257296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (700975968).

643257296 is an abundant number, since it is smaller than the sum of its proper divisors (758694640).

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

643257296 is a wasteful number, since it uses less digits than its factorization.

643257296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7800 (or 7783 counting only the distinct ones).

The product of its digits is 544320, while the sum is 44.

The square root of 643257296 is about 25362.5175406544. The cubic root of 643257296 is about 863.2334092579.

The spelling of 643257296 in words is "six hundred forty-three million, two hundred fifty-seven thousand, two hundred ninety-six".