1378726189 has 2 divisors, whose sum is σ = 1378726190. Its totient is φ = 1378726188.

The previous prime is 1378726171. The next prime is 1378726289. The reversal of 1378726189 is 9816278731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1222900900 + 155825289 = 34970^2 + 12483^2 .

It is a cyclic number.

It is not a de Polignac number, because 1378726189 - 2²⁹ = 841855277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1378726109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689363094 + 689363095.

It is an arithmetic number, because the mean of its divisors is an integer number (689363095).

Almost surely, 2^1378726189 is an apocalyptic number.

It is an amenable number.

1378726189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378726189 is an equidigital number, since it uses as much as digits as its factorization.

1378726189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1016064, while the sum is 52.

The square root of 1378726189 is about 37131.2023640496. The cubic root of 1378726189 is about 1112.9936205120.

The spelling of 1378726189 in words is "one billion, three hundred seventy-eight million, seven hundred twenty-six thousand, one hundred eighty-nine".