138408269789 has 2 divisors, whose sum is σ = 138408269790. Its totient is φ = 138408269788.

The previous prime is 138408269777. The next prime is 138408269863. The reversal of 138408269789 is 987962804831.

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., 95013130564 + 43395139225 = 308242^2 + 208315^2 .

It is a cyclic number.

It is not a de Polignac number, because 138408269789 - 2⁴ = 138408269773 is a prime.

It is a super-2 number, since 2×138408269789² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138408269719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69204134894 + 69204134895.

It is an arithmetic number, because the mean of its divisors is an integer number (69204134895).

Almost surely, 2^138408269789 is an apocalyptic number.

It is an amenable number.

138408269789 is a deficient number, since it is larger than the sum of its proper divisors (1).

138408269789 is an equidigital number, since it uses as much as digits as its factorization.

138408269789 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41803776, while the sum is 65.

The spelling of 138408269789 in words is "one hundred thirty-eight billion, four hundred eight million, two hundred sixty-nine thousand, seven hundred eighty-nine".