643155189 has 4 divisors (see below), whose sum is σ = 857540256. Its totient is φ = 428770124.

The previous prime is 643155179. The next prime is 643155193. The reversal of 643155189 is 981551346.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 643155189 - 2⁵ = 643155157 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 643155189.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643155179) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107192529 + ... + 107192534.

It is an arithmetic number, because the mean of its divisors is an integer number (214385064).

Almost surely, 2^643155189 is an apocalyptic number.

It is an amenable number.

643155189 is a deficient number, since it is larger than the sum of its proper divisors (214385067).

643155189 is a wasteful number, since it uses less digits than its factorization.

643155189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214385066.

The product of its digits is 129600, while the sum is 42.

The square root of 643155189 is about 25360.5045099659. The cubic root of 643155189 is about 863.1877319225.

The spelling of 643155189 in words is "six hundred forty-three million, one hundred fifty-five thousand, one hundred eighty-nine".