643473379 has 2 divisors, whose sum is σ = 643473380. Its totient is φ = 643473378.

The previous prime is 643473377. The next prime is 643473419. The reversal of 643473379 is 973374346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643473379 - 2¹ = 643473377 is a prime.

Together with 643473377, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (643473377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321736689 + 321736690.

It is an arithmetic number, because the mean of its divisors is an integer number (321736690).

Almost surely, 2^643473379 is an apocalyptic number.

643473379 is a deficient number, since it is larger than the sum of its proper divisors (1).

643473379 is an equidigital number, since it uses as much as digits as its factorization.

643473379 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1143072, while the sum is 46.

The square root of 643473379 is about 25366.7770715950. Note that the first 3 decimals coincide. The cubic root of 643473379 is about 863.3300575631.

The spelling of 643473379 in words is "six hundred forty-three million, four hundred seventy-three thousand, three hundred seventy-nine".