640578435 has 32 divisors (see below), whose sum is σ = 1179919872. Its totient is φ = 290691840.

The previous prime is 640578409. The next prime is 640578437. The reversal of 640578435 is 534875046.

640578435 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640578435 - 2⁵ = 640578403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640578437) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7881 + ... + 36650.

It is an arithmetic number, because the mean of its divisors is an integer number (36872496).

Almost surely, 2^640578435 is an apocalyptic number.

640578435 is a deficient number, since it is larger than the sum of its proper divisors (539341437).

640578435 is a wasteful number, since it uses less digits than its factorization.

640578435 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44683.

The product of its (nonzero) digits is 403200, while the sum is 42.

The square root of 640578435 is about 25309.6510248561. The cubic root of 640578435 is about 862.0334229248.

The spelling of 640578435 in words is "six hundred forty million, five hundred seventy-eight thousand, four hundred thirty-five".