138774121 has 2 divisors, whose sum is σ = 138774122. Its totient is φ = 138774120.

The previous prime is 138774107. The next prime is 138774137. The reversal of 138774121 is 121477831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122412096 + 16362025 = 11064^2 + 4045^2 .

It is an emirp because it is prime and its reverse (121477831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138774121 - 2⁷ = 138773993 is a prime.

It is not a weakly prime, because it can be changed into another prime (138774151) 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, 69387060 + 69387061.

It is an arithmetic number, because the mean of its divisors is an integer number (69387061).

Almost surely, 2^138774121 is an apocalyptic number.

It is an amenable number.

138774121 is a deficient number, since it is larger than the sum of its proper divisors (1).

138774121 is an equidigital number, since it uses as much as digits as its factorization.

138774121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9408, while the sum is 34.

The square root of 138774121 is about 11780.2428243224. The cubic root of 138774121 is about 517.7294008113.

The spelling of 138774121 in words is "one hundred thirty-eight million, seven hundred seventy-four thousand, one hundred twenty-one".