640434575 has 24 divisors (see below), whose sum is σ = 879288960. Its totient is φ = 458805600.

The previous prime is 640434541. The next prime is 640434581. The reversal of 640434575 is 575434046.

It is a happy number.

It is not a de Polignac number, because 640434575 - 2⁶ = 640434511 is a prime.

It is a super-3 number, since 3×640434575³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1046 + ... + 35804.

It is an arithmetic number, because the mean of its divisors is an integer number (36637040).

Almost surely, 2^640434575 is an apocalyptic number.

640434575 is a deficient number, since it is larger than the sum of its proper divisors (238854385).

640434575 is a wasteful number, since it uses less digits than its factorization.

640434575 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34847 (or 34842 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 38.

The square root of 640434575 is about 25306.8088663901. The cubic root of 640434575 is about 861.9688867670.

The spelling of 640434575 in words is "six hundred forty million, four hundred thirty-four thousand, five hundred seventy-five".