643484667 has 8 divisors (see below), whose sum is σ = 980548096. Its totient is φ = 367705512.

The previous prime is 643484617. The next prime is 643484671. The reversal of 643484667 is 766484346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 643484667 - 2⁶ = 643484603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643484617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15321043 + ... + 15321084.

It is an arithmetic number, because the mean of its divisors is an integer number (122568512).

Almost surely, 2^643484667 is an apocalyptic number.

643484667 is a deficient number, since it is larger than the sum of its proper divisors (337063429).

643484667 is a wasteful number, since it uses less digits than its factorization.

643484667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30642137.

The product of its digits is 2322432, while the sum is 48.

The square root of 643484667 is about 25366.9995663657. Note that the first 3 decimals coincide. The cubic root of 643484667 is about 863.3351057971.

The spelling of 643484667 in words is "six hundred forty-three million, four hundred eighty-four thousand, six hundred sixty-seven".