643542112400 has 120 divisors (see below), whose sum is σ = 1690106210208. Its totient is φ = 233537920000.

The previous prime is 643542112303. The next prime is 643542112427. The reversal of 643542112400 is 4211245346.

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 23 ways as a sum of consecutive naturals, for example, 2011460 + ... + 2309340.

Almost surely, 2^643542112400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643542112400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (845053105104).

643542112400 is an abundant number, since it is smaller than the sum of its proper divisors (1046564097808).

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

643542112400 is a wasteful number, since it uses less digits than its factorization.

643542112400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298401 (or 298390 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

Adding to 643542112400 its reverse (4211245346), we get a palindrome (647753357746).

The spelling of 643542112400 in words is "six hundred forty-three billion, five hundred forty-two million, one hundred twelve thousand, four hundred".