643125243 has 32 divisors (see below), whose sum is σ = 931138560. Its totient is φ = 393513120.

The previous prime is 643125239. The next prime is 643125253. The reversal of 643125243 is 342521346.

It is not a de Polignac number, because 643125243 - 2² = 643125239 is a prime.

It is a super-2 number, since 2×643125243² = 827220156367618098, which contains 22 as substring.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 643125243.

It is not an unprimeable number, because it can be changed into a prime (643125253) 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 31 ways as a sum of consecutive naturals, for example, 320080 + ... + 322082.

It is an arithmetic number, because the mean of its divisors is an integer number (29098080).

Almost surely, 2^643125243 is an apocalyptic number.

643125243 is a deficient number, since it is larger than the sum of its proper divisors (288013317).

643125243 is a wasteful number, since it uses less digits than its factorization.

643125243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2199.

The product of its digits is 17280, while the sum is 30.

The square root of 643125243 is about 25359.9140968577. The cubic root of 643125243 is about 863.1743347303.

Adding to 643125243 its reverse (342521346), we get a palindrome (985646589).

The spelling of 643125243 in words is "six hundred forty-three million, one hundred twenty-five thousand, two hundred forty-three".