640462655644 has 24 divisors (see below), whose sum is σ = 1282552960640. Its totient is φ = 274135213296.

The previous prime is 640462655633. The next prime is 640462655663. The reversal of 640462655644 is 446556264046.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 640462655591 and 640462655600.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14510154 + ... + 14554225.

Almost surely, 2^640462655644 is an apocalyptic number.

It is an amenable number.

640462655644 is an abundant number, since it is smaller than the sum of its proper divisors (642090304996).

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

640462655644 is a wasteful number, since it uses less digits than its factorization.

640462655644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29065177 (or 29065175 counting only the distinct ones).

The product of its (nonzero) digits is 16588800, while the sum is 52.

The spelling of 640462655644 in words is "six hundred forty billion, four hundred sixty-two million, six hundred fifty-five thousand, six hundred forty-four".