138670789 has 4 divisors (see below), whose sum is σ = 138850956. Its totient is φ = 138490624.

The previous prime is 138670787. The next prime is 138670793. The reversal of 138670789 is 987076831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8025889 + 130644900 = 2833^2 + 11430^2 .

It is a cyclic number.

It is not a de Polignac number, because 138670789 - 2¹ = 138670787 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138670787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88924 + ... + 90469.

It is an arithmetic number, because the mean of its divisors is an integer number (34712739).

Almost surely, 2^138670789 is an apocalyptic number.

It is an amenable number.

138670789 is a deficient number, since it is larger than the sum of its proper divisors (180167).

138670789 is an equidigital number, since it uses as much as digits as its factorization.

138670789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180166.

The product of its (nonzero) digits is 508032, while the sum is 49.

The square root of 138670789 is about 11775.8561896789. The cubic root of 138670789 is about 517.6008674847.

The spelling of 138670789 in words is "one hundred thirty-eight million, six hundred seventy thousand, seven hundred eighty-nine".