12640279992 has 64 divisors (see below), whose sum is σ = 32443437600. Its totient is φ = 4101519360.

The previous prime is 12640279973. The next prime is 12640279999. The reversal of 12640279992 is 29997204621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12640279999) 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, 435634 + ... + 463742.

Almost surely, 2^12640279992 is an apocalyptic number.

12640279992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12640279992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16221718800).

12640279992 is an abundant number, since it is smaller than the sum of its proper divisors (19803157608).

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

12640279992 is a wasteful number, since it uses less digits than its factorization.

12640279992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28616 (or 28612 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 51.

The spelling of 12640279992 in words is "twelve billion, six hundred forty million, two hundred seventy-nine thousand, nine hundred ninety-two".