643253040 has 60 divisors (see below), whose sum is σ = 2160260544. Its totient is φ = 171533952.

The previous prime is 643253033. The next prime is 643253041. The reversal of 643253040 is 40352346.

643253040 is a `hidden beast` number, since 64 + 32 + 530 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a junction number, because it is equal to n+sod(n) for n = 643252995 and 643253013.

It is not an unprimeable number, because it can be changed into a prime (643253041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 445984 + ... + 447423.

Almost surely, 2^643253040 is an apocalyptic number.

643253040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

643253040 is an abundant number, since it is smaller than the sum of its proper divisors (1517007504).

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

643253040 is a wasteful number, since it uses less digits than its factorization.

643253040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 893426 (or 893417 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 27.

The square root of 643253040 is about 25362.4336371729. The cubic root of 643253040 is about 863.2315054425.

The spelling of 643253040 in words is "six hundred forty-three million, two hundred fifty-three thousand, forty".