643282399 has 2 divisors, whose sum is σ = 643282400. Its totient is φ = 643282398.

The previous prime is 643282327. The next prime is 643282403. The reversal of 643282399 is 993282346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643282399 - 2¹³ = 643274207 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643285399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321641199 + 321641200.

It is an arithmetic number, because the mean of its divisors is an integer number (321641200).

Almost surely, 2^643282399 is an apocalyptic number.

643282399 is a deficient number, since it is larger than the sum of its proper divisors (1).

643282399 is an equidigital number, since it uses as much as digits as its factorization.

643282399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 46.

The square root of 643282399 is about 25363.0124196634. The cubic root of 643282399 is about 863.2446382879.

It can be divided in two parts, 6432 and 82399, that added together give a triangular number (88831 = T₄₂₁).

The spelling of 643282399 in words is "six hundred forty-three million, two hundred eighty-two thousand, three hundred ninety-nine".