12640401220 has 48 divisors (see below), whose sum is σ = 27221443200. Its totient is φ = 4928887040.

The previous prime is 12640401199. The next prime is 12640401227. The reversal of 12640401220 is 2210404621.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 12640401191 and 12640401200.

It is not an unprimeable number, because it can be changed into a prime (12640401227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76371 + ... + 176389.

It is an arithmetic number, because the mean of its divisors is an integer number (567113400).

Almost surely, 2^12640401220 is an apocalyptic number.

12640401220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12640401220 is an abundant number, since it is smaller than the sum of its proper divisors (14581041980).

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

12640401220 is a wasteful number, since it uses less digits than its factorization.

12640401220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100188 (or 100186 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 12640401220 its reverse (2210404621), we get a palindrome (14850805841).

The spelling of 12640401220 in words is "twelve billion, six hundred forty million, four hundred one thousand, two hundred twenty".