640134361 has 8 divisors (see below), whose sum is σ = 644905800. Its totient is φ = 635378688.

The previous prime is 640134349. The next prime is 640134401. The reversal of 640134361 is 163431046.

It can be written as a sum of positive squares in 4 ways, for example, as 362712025 + 277422336 = 19045^2 + 16656^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 640134361 - 2⁷ = 640134233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640134311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84835 + ... + 92071.

It is an arithmetic number, because the mean of its divisors is an integer number (80613225).

Almost surely, 2^640134361 is an apocalyptic number.

It is an amenable number.

640134361 is a deficient number, since it is larger than the sum of its proper divisors (4771439).

640134361 is a wasteful number, since it uses less digits than its factorization.

640134361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7883.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 640134361 is about 25300.8766844155. The cubic root of 640134361 is about 861.8341784595.

The spelling of 640134361 in words is "six hundred forty million, one hundred thirty-four thousand, three hundred sixty-one".