138038778 has 24 divisors (see below), whose sum is σ = 312088608. Its totient is φ = 44012232.

The previous prime is 138038777. The next prime is 138038783. The reversal of 138038778 is 877830831.

It is not an unprimeable number, because it can be changed into a prime (138038773) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166300 + ... + 167127.

It is an arithmetic number, because the mean of its divisors is an integer number (13003692).

Almost surely, 2^138038778 is an apocalyptic number.

138038778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

138038778 is an abundant number, since it is smaller than the sum of its proper divisors (174049830).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138038778 is a wasteful number, since it uses less digits than its factorization.

138038778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333458 (or 333455 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 138038778 is about 11748.9905098268. The cubic root of 138038778 is about 516.8133243513.

The spelling of 138038778 in words is "one hundred thirty-eight million, thirty-eight thousand, seven hundred seventy-eight".