643644035040 has 192 divisors, whose sum is σ = 2037421596672. Its totient is φ = 170798284800.

The previous prime is 643644035029. The next prime is 643644035051. The reversal of 643644035040 is 40530446346.

643644035040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (643644035029) and next prime (643644035051).

It is a self number, because there is not a number n which added to its sum of digits gives 643644035040.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 128906784 + ... + 128911776.

It is an arithmetic number, because the mean of its divisors is an integer number (10611570816).

Almost surely, 2^643644035040 is an apocalyptic number.

643644035040 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 643644035040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1018710798336).

643644035040 is an abundant number, since it is smaller than the sum of its proper divisors (1393777561632).

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

643644035040 is a wasteful number, since it uses less digits than its factorization.

643644035040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6273 (or 6265 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 39.

The spelling of 643644035040 in words is "six hundred forty-three billion, six hundred forty-four million, thirty-five thousand, forty".