2638661389 has 12 divisors (see below), whose sum is σ = 3265428576. Its totient is φ = 2087731152.

The previous prime is 2638661381. The next prime is 2638661411. The reversal of 2638661389 is 9831668362.

2638661389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2638661389 - 2³ = 2638661381 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 (2638661381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1114059 + ... + 1116424.

It is an arithmetic number, because the mean of its divisors is an integer number (272119048).

Almost surely, 2^2638661389 is an apocalyptic number.

It is an amenable number.

2638661389 is a deficient number, since it is larger than the sum of its proper divisors (626767187).

2638661389 is a wasteful number, since it uses less digits than its factorization.

2638661389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2230516 (or 2230503 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 52.

The square root of 2638661389 is about 51367.9023223647. The cubic root of 2638661389 is about 1381.8510113443.

The spelling of 2638661389 in words is "two billion, six hundred thirty-eight million, six hundred sixty-one thousand, three hundred eighty-nine".