138211907 has 2 divisors, whose sum is σ = 138211908. Its totient is φ = 138211906.

The previous prime is 138211903. The next prime is 138211939. The reversal of 138211907 is 709112831.

It is an a-pointer prime, because the next prime (138211939) can be obtained adding 138211907 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138211907 - 2² = 138211903 is a prime.

It is not a weakly prime, because it can be changed into another prime (138211903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69105953 + 69105954.

It is an arithmetic number, because the mean of its divisors is an integer number (69105954).

Almost surely, 2^138211907 is an apocalyptic number.

138211907 is a deficient number, since it is larger than the sum of its proper divisors (1).

138211907 is an equidigital number, since it uses as much as digits as its factorization.

138211907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 138211907 is about 11756.3560255719. The cubic root of 138211907 is about 517.0292974629.

The spelling of 138211907 in words is "one hundred thirty-eight million, two hundred eleven thousand, nine hundred seven".