138121069 has 2 divisors, whose sum is σ = 138121070. Its totient is φ = 138121068.

The previous prime is 138121007. The next prime is 138121091. The reversal of 138121069 is 960121831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137241225 + 879844 = 11715^2 + 938^2 .

It is a cyclic number.

It is not a de Polignac number, because 138121069 - 2¹¹ = 138119021 is a prime.

It is a super-2 number, since 2×138121069² = 38154859403405522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 138121069.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138121099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69060534 + 69060535.

It is an arithmetic number, because the mean of its divisors is an integer number (69060535).

Almost surely, 2^138121069 is an apocalyptic number.

It is an amenable number.

138121069 is a deficient number, since it is larger than the sum of its proper divisors (1).

138121069 is an equidigital number, since it uses as much as digits as its factorization.

138121069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 138121069 is about 11752.4920336072. The cubic root of 138121069 is about 516.9160023512.

The spelling of 138121069 in words is "one hundred thirty-eight million, one hundred twenty-one thousand, sixty-nine".