2640817979 has 8 divisors (see below), whose sum is σ = 2766120192. Its totient is φ = 2516389480.

The previous prime is 2640817969. The next prime is 2640818017. The reversal of 2640817979 is 9797180462.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2640817979 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2640817979.

It is not an unprimeable number, because it can be changed into a prime (2640817969) 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, 212237 + ... + 224334.

It is an arithmetic number, because the mean of its divisors is an integer number (345765024).

Almost surely, 2^2640817979 is an apocalyptic number.

2640817979 is a deficient number, since it is larger than the sum of its proper divisors (125302213).

2640817979 is a wasteful number, since it uses less digits than its factorization.

2640817979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436857.

The product of its (nonzero) digits is 1524096, while the sum is 53.

The square root of 2640817979 is about 51388.8896455255. The cubic root of 2640817979 is about 1382.2273732089.

The spelling of 2640817979 in words is "two billion, six hundred forty million, eight hundred seventeen thousand, nine hundred seventy-nine".