640675071 has 6 divisors (see below), whose sum is σ = 925419560. Its totient is φ = 427116708.

The previous prime is 640675037. The next prime is 640675093. The reversal of 640675071 is 170576046.

640675071 is a `hidden beast` number, since 640 + 6 + 7 + 5 + 0 + 7 + 1 = 666.

It is not a de Polignac number, because 640675071 - 2¹⁴ = 640658687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640675271) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35593051 + ... + 35593068.

Almost surely, 2^640675071 is an apocalyptic number.

640675071 is a deficient number, since it is larger than the sum of its proper divisors (284744489).

640675071 is a wasteful number, since it uses less digits than its factorization.

640675071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71186125 (or 71186122 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 640675071 is about 25311.5600269916. The cubic root of 640675071 is about 862.0767687867.

The spelling of 640675071 in words is "six hundred forty million, six hundred seventy-five thousand, seventy-one".