640621218313 has 8 divisors (see below), whose sum is σ = 681914959200. Its totient is φ = 600085160928.

The previous prime is 640621218311. The next prime is 640621218317. The reversal of 640621218313 is 313812126046.

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 640621218313 - 2¹ = 640621218311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640621218311) 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, 189419131 + ... + 189422512.

It is an arithmetic number, because the mean of its divisors is an integer number (85239369900).

Almost surely, 2^640621218313 is an apocalyptic number.

It is an amenable number.

640621218313 is a deficient number, since it is larger than the sum of its proper divisors (41293740887).

640621218313 is a wasteful number, since it uses less digits than its factorization.

640621218313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378841751.

The product of its (nonzero) digits is 41472, while the sum is 37.

The spelling of 640621218313 in words is "six hundred forty billion, six hundred twenty-one million, two hundred eighteen thousand, three hundred thirteen".