138545489 has 2 divisors, whose sum is σ = 138545490. Its totient is φ = 138545488.

The previous prime is 138545483. The next prime is 138545531. The reversal of 138545489 is 984545831.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77440000 + 61105489 = 8800^2 + 7817^2 .

It is an emirp because it is prime and its reverse (984545831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138545489 - 2¹² = 138541393 is a prime.

It is not a weakly prime, because it can be changed into another prime (138545483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69272744 + 69272745.

It is an arithmetic number, because the mean of its divisors is an integer number (69272745).

Almost surely, 2^138545489 is an apocalyptic number.

It is an amenable number.

138545489 is a deficient number, since it is larger than the sum of its proper divisors (1).

138545489 is an equidigital number, since it uses as much as digits as its factorization.

138545489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 691200, while the sum is 47.

The square root of 138545489 is about 11770.5347796946. The cubic root of 138545489 is about 517.4449227637. Note that the first 3 decimals are identical.

The spelling of 138545489 in words is "one hundred thirty-eight million, five hundred forty-five thousand, four hundred eighty-nine".