640630455340 has 36 divisors (see below), whose sum is σ = 1374556984416. Its totient is φ = 250799990752.

The previous prime is 640630455331. The next prime is 640630455341. The reversal of 640630455340 is 43554036046.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 640630455293 and 640630455302.

It is not an unprimeable number, because it can be changed into a prime (640630455341) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7206052 + ... + 7294411.

It is an arithmetic number, because the mean of its divisors is an integer number (38182138456).

Almost surely, 2^640630455340 is an apocalyptic number.

It is an amenable number.

640630455340 is an abundant number, since it is smaller than the sum of its proper divisors (733926529076).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640630455340 is a wasteful number, since it uses less digits than its factorization.

640630455340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14500566 (or 14500517 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 40.

The spelling of 640630455340 in words is "six hundred forty billion, six hundred thirty million, four hundred fifty-five thousand, three hundred forty".