1389666186 has 16 divisors (see below), whose sum is σ = 3088147200. Its totient is φ = 463222044.

The previous prime is 1389666181. The next prime is 1389666191. The reversal of 1389666186 is 6816669831.

It is an interprime number because it is at equal distance from previous prime (1389666181) and next prime (1389666191).

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 25734559 = 1389666186 / (1 + 3 + 8 + 9 + 6 + 6 + 6 + 1 + 8 + 6).

It is not an unprimeable number, because it can be changed into a prime (1389666181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12867226 + ... + 12867333.

It is an arithmetic number, because the mean of its divisors is an integer number (193009200).

Almost surely, 2^1389666186 is an apocalyptic number.

1389666186 is an abundant number, since it is smaller than the sum of its proper divisors (1698481014).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1389666186 is a wasteful number, since it uses less digits than its factorization.

1389666186 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25734570 (or 25734564 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 54.

The square root of 1389666186 is about 37278.2267013870. The cubic root of 1389666186 is about 1115.9296839730.

The spelling of 1389666186 in words is "one billion, three hundred eighty-nine million, six hundred sixty-six thousand, one hundred eighty-six".