1380648779 has 2 divisors, whose sum is σ = 1380648780. Its totient is φ = 1380648778.

The previous prime is 1380648769. The next prime is 1380648799. The reversal of 1380648779 is 9778460831.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1380648779 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1380648779.

It is not a weakly prime, because it can be changed into another prime (1380648769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690324389 + 690324390.

It is an arithmetic number, because the mean of its divisors is an integer number (690324390).

Almost surely, 2^1380648779 is an apocalyptic number.

1380648779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1380648779 is an equidigital number, since it uses as much as digits as its factorization.

1380648779 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2032128, while the sum is 53.

The square root of 1380648779 is about 37157.0824877304. The cubic root of 1380648779 is about 1113.5107250079.

The spelling of 1380648779 in words is "one billion, three hundred eighty million, six hundred forty-eight thousand, seven hundred seventy-nine".