138481789 has 2 divisors, whose sum is σ = 138481790. Its totient is φ = 138481788.

The previous prime is 138481771. The next prime is 138481793. The reversal of 138481789 is 987184831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138415225 + 66564 = 11765^2 + 258^2 .

It is an emirp because it is prime and its reverse (987184831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138481789 - 2⁷ = 138481661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138481799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69240894 + 69240895.

It is an arithmetic number, because the mean of its divisors is an integer number (69240895).

Almost surely, 2^138481789 is an apocalyptic number.

It is an amenable number.

138481789 is a deficient number, since it is larger than the sum of its proper divisors (1).

138481789 is an equidigital number, since it uses as much as digits as its factorization.

138481789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 387072, while the sum is 49.

The square root of 138481789 is about 11767.8285592543. The cubic root of 138481789 is about 517.3656075517.

The spelling of 138481789 in words is "one hundred thirty-eight million, four hundred eighty-one thousand, seven hundred eighty-nine".