640512541 has 2 divisors, whose sum is σ = 640512542. Its totient is φ = 640512540.

The previous prime is 640512529. The next prime is 640512557. The reversal of 640512541 is 145215046.

640512541 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 635544100 + 4968441 = 25210^2 + 2229^2 .

It is a cyclic number.

It is not a de Polignac number, because 640512541 - 2⁷ = 640512413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640512511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320256270 + 320256271.

It is an arithmetic number, because the mean of its divisors is an integer number (320256271).

Almost surely, 2^640512541 is an apocalyptic number.

It is an amenable number.

640512541 is a deficient number, since it is larger than the sum of its proper divisors (1).

640512541 is an equidigital number, since it uses as much as digits as its factorization.

640512541 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 640512541 is about 25308.3492349857. The cubic root of 640512541 is about 862.0038638185.

Adding to 640512541 its reverse (145215046), we get a palindrome (785727587).

The spelling of 640512541 in words is "six hundred forty million, five hundred twelve thousand, five hundred forty-one".