640163451244 has 12 divisors (see below), whose sum is σ = 1120296364264. Its totient is φ = 320078775744.

The previous prime is 640163451223. The next prime is 640163451269. The reversal of 640163451244 is 442154361046.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 640163451197 and 640163451206.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206754 + ... + 1150249.

Almost surely, 2^640163451244 is an apocalyptic number.

It is an amenable number.

640163451244 is a deficient number, since it is larger than the sum of its proper divisors (480132913020).

640163451244 is a wasteful number, since it uses less digits than its factorization.

640163451244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1474944 (or 1474942 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 40.

The spelling of 640163451244 in words is "six hundred forty billion, one hundred sixty-three million, four hundred fifty-one thousand, two hundred forty-four".