12640279997 has 8 divisors (see below), whose sum is σ = 12977094240. Its totient is φ = 12307107280.

The previous prime is 12640279973. The next prime is 12640279999. The reversal of 12640279997 is 79997204621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12640279997 - 2¹⁸ = 12640017853 is a prime.

It is a Duffinian number.

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 7 ways as a sum of consecutive naturals, for example, 903347 + ... + 917232.

It is an arithmetic number, because the mean of its divisors is an integer number (1622136780).

Almost surely, 2^12640279997 is an apocalyptic number.

It is an amenable number.

12640279997 is a deficient number, since it is larger than the sum of its proper divisors (336814243).

12640279997 is a wasteful number, since it uses less digits than its factorization.

12640279997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1820763.

The product of its (nonzero) digits is 3429216, while the sum is 56.

The spelling of 12640279997 in words is "twelve billion, six hundred forty million, two hundred seventy-nine thousand, nine hundred ninety-seven".