643221300252 has 12 divisors (see below), whose sum is σ = 1500849700616. Its totient is φ = 214407100080.

The previous prime is 643221300251. The next prime is 643221300349. The reversal of 643221300252 is 252003122346.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-3 number, since 3×643221300252³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643221300251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26800887499 + ... + 26800887522.

Almost surely, 2^643221300252 is an apocalyptic number.

It is an amenable number.

643221300252 is an abundant number, since it is smaller than the sum of its proper divisors (857628400364).

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

643221300252 is a wasteful number, since it uses less digits than its factorization.

643221300252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53601775028 (or 53601775026 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

Adding to 643221300252 its reverse (252003122346), we get a palindrome (895224422598).

The spelling of 643221300252 in words is "six hundred forty-three billion, two hundred twenty-one million, three hundred thousand, two hundred fifty-two".