643321353 has 8 divisors (see below), whose sum is σ = 857883808. Its totient is φ = 428819904.

The previous prime is 643321307. The next prime is 643321381. The reversal of 643321353 is 353123346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 643321353 - 2⁸ = 643321097 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 643321353.

It is not an unprimeable number, because it can be changed into a prime (643321453) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23226 + ... + 42732.

It is an arithmetic number, because the mean of its divisors is an integer number (107235476).

Almost surely, 2^643321353 is an apocalyptic number.

It is an amenable number.

643321353 is a deficient number, since it is larger than the sum of its proper divisors (214562455).

643321353 is a wasteful number, since it uses less digits than its factorization.

643321353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30503.

The product of its digits is 19440, while the sum is 30.

The square root of 643321353 is about 25363.7803373235. The cubic root of 643321353 is about 863.2620625446.

Adding to 643321353 its reverse (353123346), we get a palindrome (996444699).

The spelling of 643321353 in words is "six hundred forty-three million, three hundred twenty-one thousand, three hundred fifty-three".