2638979689 has 2 divisors, whose sum is σ = 2638979690. Its totient is φ = 2638979688.

The previous prime is 2638979633. The next prime is 2638979701. The reversal of 2638979689 is 9869798362.

2638979689 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2277675625 + 361304064 = 47725^2 + 19008^2 .

It is a cyclic number.

It is not a de Polignac number, because 2638979689 - 2⁹ = 2638979177 is a prime.

It is not a weakly prime, because it can be changed into another prime (2638179689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319489844 + 1319489845.

It is an arithmetic number, because the mean of its divisors is an integer number (1319489845).

Almost surely, 2^2638979689 is an apocalyptic number.

It is an amenable number.

2638979689 is a deficient number, since it is larger than the sum of its proper divisors (1).

2638979689 is an equidigital number, since it uses as much as digits as its factorization.

2638979689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 70543872, while the sum is 67.

The square root of 2638979689 is about 51371.0004671897. Note that the first 3 decimals coincide. The cubic root of 2638979689 is about 1381.9065730385.

The spelling of 2638979689 in words is "two billion, six hundred thirty-eight million, nine hundred seventy-nine thousand, six hundred eighty-nine".