643777089 has 8 divisors (see below), whose sum is σ = 866703552. Its totient is φ = 425017680.

The previous prime is 643777081. The next prime is 643777091. The reversal of 643777089 is 980777346.

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

It is not a de Polignac number, because 643777089 - 2³ = 643777081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643777081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1041402 + ... + 1042019.

It is an arithmetic number, because the mean of its divisors is an integer number (108337944).

Almost surely, 2^643777089 is an apocalyptic number.

It is an amenable number.

643777089 is a deficient number, since it is larger than the sum of its proper divisors (222926463).

643777089 is a wasteful number, since it uses less digits than its factorization.

643777089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2083527.

The product of its (nonzero) digits is 1778112, while the sum is 51.

The square root of 643777089 is about 25372.7627388111. The cubic root of 643777089 is about 863.4658625755.

The spelling of 643777089 in words is "six hundred forty-three million, seven hundred seventy-seven thousand, eighty-nine".