138194688 has 72 divisors (see below), whose sum is σ = 371582848. Its totient is φ = 45591552.

The previous prime is 138194687. The next prime is 138194699. The reversal of 138194688 is 886491831.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138194681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78231 + ... + 79977.

Almost surely, 2^138194688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138194688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185791424).

138194688 is an abundant number, since it is smaller than the sum of its proper divisors (233388160).

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

138194688 is a wasteful number, since it uses less digits than its factorization.

138194688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1869 (or 1855 counting only the distinct ones).

The product of its digits is 331776, while the sum is 48.

The square root of 138194688 is about 11755.6236755010. The cubic root of 138194688 is about 517.0078253688.

It can be divided in two parts, 1381 and 94688, that added together give a palindrome (96069).

The spelling of 138194688 in words is "one hundred thirty-eight million, one hundred ninety-four thousand, six hundred eighty-eight".