643340012120 has 128 divisors (see below), whose sum is σ = 1577225260800. Its totient is φ = 234759181824.

The previous prime is 643340012069. The next prime is 643340012131. The reversal of 643340012120 is 21210043346.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 643340012120.

It is a congruent number.

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, 15150839 + ... + 15193241.

It is an arithmetic number, because the mean of its divisors is an integer number (12322072350).

Almost surely, 2^643340012120 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 643340012120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (788612630400).

643340012120 is an abundant number, since it is smaller than the sum of its proper divisors (933885248680).

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

643340012120 is a wasteful number, since it uses less digits than its factorization.

643340012120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42769 (or 42765 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 643340012120 its reverse (21210043346), we get a palindrome (664550055466).

The spelling of 643340012120 in words is "six hundred forty-three billion, three hundred forty million, twelve thousand, one hundred twenty".