643255426212 has 96 divisors (see below), whose sum is σ = 1819847393280. Its totient is φ = 172743217920.

The previous prime is 643255426199. The next prime is 643255426273. The reversal of 643255426212 is 212624552346.

It is a Harshad number since it is a multiple of its sum of digits (42).

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 31 ways as a sum of consecutive naturals, for example, 1384089 + ... + 1789472.

It is an arithmetic number, because the mean of its divisors is an integer number (18956743680).

Almost surely, 2^643255426212 is an apocalyptic number.

It is an amenable number.

643255426212 is an abundant number, since it is smaller than the sum of its proper divisors (1176591967068).

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

643255426212 is a wasteful number, since it uses less digits than its factorization.

643255426212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3173721 (or 3173719 counting only the distinct ones).

The product of its digits is 691200, while the sum is 42.

Adding to 643255426212 its reverse (212624552346), we get a palindrome (855879978558).

The spelling of 643255426212 in words is "six hundred forty-three billion, two hundred fifty-five million, four hundred twenty-six thousand, two hundred twelve".