643557133 has 8 divisors (see below), whose sum is σ = 649290752. Its totient is φ = 637834176.

The previous prime is 643557127. The next prime is 643557163. The reversal of 643557133 is 331755346.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643557133 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643557092 and 643557101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643557163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162766 + ... + 166672.

It is an arithmetic number, because the mean of its divisors is an integer number (81161344).

Almost surely, 2^643557133 is an apocalyptic number.

It is an amenable number.

643557133 is a deficient number, since it is larger than the sum of its proper divisors (5733619).

643557133 is a wasteful number, since it uses less digits than its factorization.

643557133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5331.

The product of its digits is 113400, while the sum is 37.

The square root of 643557133 is about 25368.4278779746. The cubic root of 643557133 is about 863.3675127301.

The spelling of 643557133 in words is "six hundred forty-three million, five hundred fifty-seven thousand, one hundred thirty-three".