640004571 has 10 divisors (see below), whose sum is σ = 956056332. Its totient is φ = 426669660.

The previous prime is 640004543. The next prime is 640004587. The reversal of 640004571 is 175400046.

It is not a de Polignac number, because 640004571 - 2⁵ = 640004539 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (640004471) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3950565 + ... + 3950726.

Almost surely, 2^640004571 is an apocalyptic number.

640004571 is a deficient number, since it is larger than the sum of its proper divisors (316051761).

640004571 is an equidigital number, since it uses as much as digits as its factorization.

640004571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7901303 (or 7901294 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 640004571 is about 25298.3116235056. The cubic root of 640004571 is about 861.7759276581.

The spelling of 640004571 in words is "six hundred forty million, four thousand, five hundred seventy-one".