643484239 has 4 divisors (see below), whose sum is σ = 644441056. Its totient is φ = 642527424.

The previous prime is 643484227. The next prime is 643484243. The reversal of 643484239 is 932484346.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 643484239 - 2⁷ = 643484111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643484195 and 643484204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643484339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 477399 + ... + 478744.

It is an arithmetic number, because the mean of its divisors is an integer number (161110264).

Almost surely, 2^643484239 is an apocalyptic number.

643484239 is a deficient number, since it is larger than the sum of its proper divisors (956817).

643484239 is an equidigital number, since it uses as much as digits as its factorization.

643484239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956816.

The product of its digits is 497664, while the sum is 43.

The square root of 643484239 is about 25366.9911302070. The cubic root of 643484239 is about 863.3349143875.

The spelling of 643484239 in words is "six hundred forty-three million, four hundred eighty-four thousand, two hundred thirty-nine".