640463544240 has 320 divisors, whose sum is σ = 2242692458496. Its totient is φ = 150126759936.

The previous prime is 640463544221. The next prime is 640463544251. The reversal of 640463544240 is 42445364046.

It is a happy number.

640463544240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 640463544192 and 640463544201.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5366659 + ... + 5484701.

Almost surely, 2^640463544240 is an apocalyptic number.

640463544240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640463544240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1121346229248).

640463544240 is an abundant number, since it is smaller than the sum of its proper divisors (1602228914256).

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

640463544240 is a wasteful number, since it uses less digits than its factorization.

640463544240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118156 (or 118150 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 42.

The spelling of 640463544240 in words is "six hundred forty billion, four hundred sixty-three million, five hundred forty-four thousand, two hundred forty".