138439867 has 2 divisors, whose sum is σ = 138439868. Its totient is φ = 138439866.

The previous prime is 138439859. The next prime is 138439877. The reversal of 138439867 is 768934831.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138439867 - 2³ = 138439859 is a prime.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 138439867.

It is not a weakly prime, because it can be changed into another prime (138439817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69219933 + 69219934.

It is an arithmetic number, because the mean of its divisors is an integer number (69219934).

Almost surely, 2^138439867 is an apocalyptic number.

138439867 is a deficient number, since it is larger than the sum of its proper divisors (1).

138439867 is an equidigital number, since it uses as much as digits as its factorization.

138439867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 870912, while the sum is 49.

The square root of 138439867 is about 11766.0472122119. The cubic root of 138439867 is about 517.3133956565.

The spelling of 138439867 in words is "one hundred thirty-eight million, four hundred thirty-nine thousand, eight hundred sixty-seven".