138489649 has 2 divisors, whose sum is σ = 138489650. Its totient is φ = 138489648.

The previous prime is 138489643. The next prime is 138489691. The reversal of 138489649 is 946984831.

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., 135303424 + 3186225 = 11632^2 + 1785^2 .

It is a cyclic number.

It is not a de Polignac number, because 138489649 - 2³ = 138489641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138489596 and 138489605.

It is not a weakly prime, because it can be changed into another prime (138489641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69244824 + 69244825.

It is an arithmetic number, because the mean of its divisors is an integer number (69244825).

Almost surely, 2^138489649 is an apocalyptic number.

It is an amenable number.

138489649 is a deficient number, since it is larger than the sum of its proper divisors (1).

138489649 is an equidigital number, since it uses as much as digits as its factorization.

138489649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1492992, while the sum is 52.

The square root of 138489649 is about 11768.1625158731. The cubic root of 138489649 is about 517.3753956420.

The spelling of 138489649 in words is "one hundred thirty-eight million, four hundred eighty-nine thousand, six hundred forty-nine".