12640279986 has 96 divisors (see below), whose sum is σ = 29740677120. Its totient is φ = 3978893664.

The previous prime is 12640279973. The next prime is 12640279999. The reversal of 12640279986 is 68997204621.

It is an interprime number because it is at equal distance from previous prime (12640279973) and next prime (12640279999).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7465356 + ... + 7467048.

It is an arithmetic number, because the mean of its divisors is an integer number (309798720).

Almost surely, 2^12640279986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12640279986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14870338560).

12640279986 is an abundant number, since it is smaller than the sum of its proper divisors (17100397134).

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

12640279986 is a wasteful number, since it uses less digits than its factorization.

12640279986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2125 (or 2100 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 12640279986 in words is "twelve billion, six hundred forty million, two hundred seventy-nine thousand, nine hundred eighty-six".