643525434 has 24 divisors (see below), whose sum is σ = 1395823572. Its totient is φ = 214274880.

The previous prime is 643525411. The next prime is 643525489. The reversal of 643525434 is 434525346.

643525434 is a `hidden beast` number, since 64 + 3 + 52 + 543 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 600005025 + 43520409 = 24495^2 + 6597^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2059 + ... + 35934.

Almost surely, 2^643525434 is an apocalyptic number.

643525434 is an abundant number, since it is smaller than the sum of its proper divisors (752298138).

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

643525434 is a wasteful number, since it uses less digits than its factorization.

643525434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38942 (or 38939 counting only the distinct ones).

The product of its digits is 172800, while the sum is 36.

The square root of 643525434 is about 25367.8030976275. The cubic root of 643525434 is about 863.3533371764.

The spelling of 643525434 in words is "six hundred forty-three million, five hundred twenty-five thousand, four hundred thirty-four".