2638990139 has 4 divisors (see below), whose sum is σ = 2639684256. Its totient is φ = 2638296024.

The previous prime is 2638990097. The next prime is 2638990147. The reversal of 2638990139 is 9310998362.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2638990139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2634990139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 341324 + ... + 348969.

It is an arithmetic number, because the mean of its divisors is an integer number (659921064).

Almost surely, 2^2638990139 is an apocalyptic number.

2638990139 is a deficient number, since it is larger than the sum of its proper divisors (694117).

2638990139 is an equidigital number, since it uses as much as digits as its factorization.

2638990139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694116.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 2638990139 is about 51371.1021781702. The cubic root of 2638990139 is about 1381.9083970900.

The spelling of 2638990139 in words is "two billion, six hundred thirty-eight million, nine hundred ninety thousand, one hundred thirty-nine".