643060667 has 2 divisors, whose sum is σ = 643060668. Its totient is φ = 643060666.

The previous prime is 643060619. The next prime is 643060697. The reversal of 643060667 is 766060346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643060667 - 2⁶ = 643060603 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643060667.

It is not a weakly prime, because it can be changed into another prime (643060697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321530333 + 321530334.

It is an arithmetic number, because the mean of its divisors is an integer number (321530334).

Almost surely, 2^643060667 is an apocalyptic number.

643060667 is a deficient number, since it is larger than the sum of its proper divisors (1).

643060667 is an equidigital number, since it uses as much as digits as its factorization.

643060667 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 38.

The square root of 643060667 is about 25358.6408744633. The cubic root of 643060667 is about 863.1454434103.

The spelling of 643060667 in words is "six hundred forty-three million, sixty thousand, six hundred sixty-seven".