640673271 has 48 divisors (see below), whose sum is σ = 1138924800. Its totient is φ = 338690304.

The previous prime is 640673269. The next prime is 640673273. The reversal of 640673271 is 172376046.

640673271 is a `hidden beast` number, since 640 + 6 + 7 + 3 + 2 + 7 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (640673269) and next prime (640673273).

It is not a de Polignac number, because 640673271 - 2¹ = 640673269 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640673273) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 58120 + ... + 68258.

It is an arithmetic number, because the mean of its divisors is an integer number (23727600).

Almost surely, 2^640673271 is an apocalyptic number.

640673271 is a deficient number, since it is larger than the sum of its proper divisors (498251529).

640673271 is a wasteful number, since it uses less digits than its factorization.

640673271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10228 (or 10225 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 36.

The square root of 640673271 is about 25311.5244700907. The cubic root of 640673271 is about 862.0759614406.

The spelling of 640673271 in words is "six hundred forty million, six hundred seventy-three thousand, two hundred seventy-one".