643241534535400 has 24 divisors (see below), whose sum is σ = 1495536567795270. Its totient is φ = 257296613814080.

The previous prime is 643241534535329. The next prime is 643241534535401. The reversal of 643241534535400 is 4535435142346.

It can be written as a sum of positive squares in 3 ways, for example, as 287708561976676 + 355532972558724 = 16961974^2 + 18855582^2 .

It is not an unprimeable number, because it can be changed into a prime (643241534535401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1608103836139 + ... + 1608103836538.

Almost surely, 2^{643241534535400} is an apocalyptic number.

It is an amenable number.

643241534535400 is an abundant number, since it is smaller than the sum of its proper divisors (852295033259870).

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

643241534535400 is a wasteful number, since it uses less digits than its factorization.

643241534535400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3216207672693 (or 3216207672684 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 49.

Adding to 643241534535400 its reverse (4535435142346), we get a palindrome (647776969677746).

The spelling of 643241534535400 in words is "six hundred forty-three trillion, two hundred forty-one billion, five hundred thirty-four million, five hundred thirty-five thousand, four hundred".