640343361 has 8 divisors (see below), whose sum is σ = 975761344. Its totient is φ = 365910480.

The previous prime is 640343359. The next prime is 640343383. The reversal of 640343361 is 163343046.

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

It is not a de Polignac number, because 640343361 - 2¹ = 640343359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640343351) 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, 15246250 + ... + 15246291.

It is an arithmetic number, because the mean of its divisors is an integer number (121970168).

Almost surely, 2^640343361 is an apocalyptic number.

It is an amenable number.

640343361 is a deficient number, since it is larger than the sum of its proper divisors (335417983).

640343361 is a wasteful number, since it uses less digits than its factorization.

640343361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30492551.

The product of its (nonzero) digits is 15552, while the sum is 30.

The square root of 640343361 is about 25305.0066390033. The cubic root of 640343361 is about 861.9279628038.

The spelling of 640343361 in words is "six hundred forty million, three hundred forty-three thousand, three hundred sixty-one".