138165449 has 8 divisors (see below), whose sum is σ = 141819720. Its totient is φ = 134524800.

The previous prime is 138165413. The next prime is 138165463. The reversal of 138165449 is 944561831.

It can be written as a sum of positive squares in 4 ways, for example, as 525625 + 137639824 = 725^2 + 11732^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138165449 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138165649) 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 7 ways as a sum of consecutive naturals, for example, 19067 + ... + 25295.

It is an arithmetic number, because the mean of its divisors is an integer number (17727465).

Almost surely, 2^138165449 is an apocalyptic number.

It is an amenable number.

138165449 is a deficient number, since it is larger than the sum of its proper divisors (3654271).

138165449 is an equidigital number, since it uses as much as digits as its factorization.

138165449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6811.

The product of its digits is 103680, while the sum is 41.

The square root of 138165449 is about 11754.3799921561. The cubic root of 138165449 is about 516.9713602478.

The spelling of 138165449 in words is "one hundred thirty-eight million, one hundred sixty-five thousand, four hundred forty-nine".