643514240 has 64 divisors (see below), whose sum is σ = 1605324960. Its totient is φ = 246208512.

The previous prime is 643514231. The next prime is 643514281. The reversal of 643514240 is 42415346.

643514240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×643514240² = 828221154165555200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7139 + ... + 36578.

Almost surely, 2^643514240 is an apocalyptic number.

It is an amenable number.

643514240 is an abundant number, since it is smaller than the sum of its proper divisors (961810720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643514240 is a wasteful number, since it uses less digits than its factorization.

643514240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43759 (or 43747 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 29.

The square root of 643514240 is about 25367.5824626629. The cubic root of 643514240 is about 863.3483311928.

Adding to 643514240 its reverse (42415346), we get a palindrome (685929586).

The spelling of 643514240 in words is "six hundred forty-three million, five hundred fourteen thousand, two hundred forty".