640457543250 has 768 divisors, whose sum is σ = 2231093329920. Its totient is φ = 134159328000.

The previous prime is 640457543239. The next prime is 640457543273. The reversal of 640457543250 is 52345754046.

640457543250 is a `hidden beast` number, since 6 + 4 + 0 + 4 + 57 + 543 + 2 + 50 = 666.

640457543250 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 640457543196 and 640457543205.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 250470972 + ... + 250473528.

It is an arithmetic number, because the mean of its divisors is an integer number (2905069440).

Almost surely, 2^640457543250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640457543250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1115546664960).

640457543250 is an abundant number, since it is smaller than the sum of its proper divisors (1590635786670).

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

640457543250 is a wasteful number, since it uses less digits than its factorization.

640457543250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2646 (or 2624 counting only the distinct ones).

The product of its (nonzero) digits is 2016000, while the sum is 45.

The spelling of 640457543250 in words is "six hundred forty billion, four hundred fifty-seven million, five hundred forty-three thousand, two hundred fifty".