138778795 has 4 divisors (see below), whose sum is σ = 166534560. Its totient is φ = 111023032.

The previous prime is 138778789. The next prime is 138778799. The reversal of 138778795 is 597877831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 597877831 = 2939 ⋅203429.

It is a cyclic number.

It is not a de Polignac number, because 138778795 - 2⁵ = 138778763 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138778799) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13877875 + ... + 13877884.

It is an arithmetic number, because the mean of its divisors is an integer number (41633640).

Almost surely, 2^138778795 is an apocalyptic number.

138778795 is a deficient number, since it is larger than the sum of its proper divisors (27755765).

138778795 is an equidigital number, since it uses as much as digits as its factorization.

138778795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27755764.

The product of its digits is 2963520, while the sum is 55.

The square root of 138778795 is about 11780.4412056595. The cubic root of 138778795 is about 517.7352132304.

The spelling of 138778795 in words is "one hundred thirty-eight million, seven hundred seventy-eight thousand, seven hundred ninety-five".