138178947 has 4 divisors (see below), whose sum is σ = 184238600. Its totient is φ = 92119296.

The previous prime is 138178933. The next prime is 138178951. The reversal of 138178947 is 749871831.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138178947 - 2⁶ = 138178883 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138178896 and 138178905.

It is not an unprimeable number, because it can be changed into a prime (138178967) 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, 23029822 + ... + 23029827.

It is an arithmetic number, because the mean of its divisors is an integer number (46059650).

Almost surely, 2^138178947 is an apocalyptic number.

138178947 is a deficient number, since it is larger than the sum of its proper divisors (46059653).

138178947 is an equidigital number, since it uses as much as digits as its factorization.

138178947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46059652.

The product of its digits is 338688, while the sum is 48.

The square root of 138178947 is about 11754.9541470820. The cubic root of 138178947 is about 516.9881947802.

The spelling of 138178947 in words is "one hundred thirty-eight million, one hundred seventy-eight thousand, nine hundred forty-seven".