643153608 has 40 divisors (see below), whose sum is σ = 1801427430. Its totient is φ = 214384320.

The previous prime is 643153607. The next prime is 643153649. The reversal of 643153608 is 806351346.

643153608 is a `hidden beast` number, since 6 + 43 + 1 + 5 + 3 + 608 = 666.

It can be written as a sum of positive squares in only one way, i.e., 398481444 + 244672164 = 19962^2 + 15642^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (643153607) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 495613 + ... + 496908.

Almost surely, 2^643153608 is an apocalyptic number.

It is an amenable number.

643153608 is an abundant number, since it is smaller than the sum of its proper divisors (1158273822).

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

643153608 is a wasteful number, since it uses less digits than its factorization.

643153608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992539 (or 992526 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 643153608 is about 25360.4733394312. The cubic root of 643153608 is about 863.1870246277.

The spelling of 643153608 in words is "six hundred forty-three million, one hundred fifty-three thousand, six hundred eight".