2608781639 has 2 divisors, whose sum is σ = 2608781640. Its totient is φ = 2608781638.

The previous prime is 2608781633. The next prime is 2608781677. The reversal of 2608781639 is 9361878062.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2608781639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2608781633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1304390819 + 1304390820.

It is an arithmetic number, because the mean of its divisors is an integer number (1304390820).

Almost surely, 2^2608781639 is an apocalyptic number.

2608781639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2608781639 is an equidigital number, since it uses as much as digits as its factorization.

2608781639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 870912, while the sum is 50.

The square root of 2608781639 is about 51076.2336023321. The cubic root of 2608781639 is about 1376.6152502520.

The spelling of 2608781639 in words is "two billion, six hundred eight million, seven hundred eighty-one thousand, six hundred thirty-nine".