643332361 has 4 divisors (see below), whose sum is σ = 735236992. Its totient is φ = 551427732.

The previous prime is 643332341. The next prime is 643332373. The reversal of 643332361 is 163233346.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 643332361 - 2⁷ = 643332233 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643332341) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 45952305 + ... + 45952318.

It is an arithmetic number, because the mean of its divisors is an integer number (183809248).

Almost surely, 2^643332361 is an apocalyptic number.

It is an amenable number.

643332361 is a deficient number, since it is larger than the sum of its proper divisors (91904631).

643332361 is an equidigital number, since it uses as much as digits as its factorization.

643332361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91904630.

The product of its digits is 23328, while the sum is 31.

The square root of 643332361 is about 25363.9973387477. The cubic root of 643332361 is about 863.2669863330.

The spelling of 643332361 in words is "six hundred forty-three million, three hundred thirty-two thousand, three hundred sixty-one".