643430768279040 has 1200 divisors, whose sum is σ = 2689566686996112. Its totient is φ = 146590124212224.

The previous prime is 643430768279027. The next prime is 643430768279041. The reversal of 643430768279040 is 40972867034346.

643430768279040 is a `hidden beast` number, since 6 + 4 + 3 + 430 + 76 + 8 + 2 + 7 + 90 + 40 = 666.

It is a super-4 number, since 4×643430768279040⁴ (a number of 60 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643430768279041) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 3119213344 + ... + 3119419616.

Almost surely, 2^{643430768279040} is an apocalyptic number.

643430768279040 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 643430768279040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1344783343498056).

643430768279040 is an abundant number, since it is smaller than the sum of its proper divisors (2046135918717072).

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

643430768279040 is a wasteful number, since it uses less digits than its factorization.

643430768279040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206629 (or 206597 counting only the distinct ones).

The product of its (nonzero) digits is 146313216, while the sum is 63.

The spelling of 643430768279040 in words is "six hundred forty-three trillion, four hundred thirty billion, seven hundred sixty-eight million, two hundred seventy-nine thousand, forty".