138738769920 has 672 divisors, whose sum is σ = 510086408832. Its totient is φ = 36160929792.

The previous prime is 138738769891. The next prime is 138738769927. The reversal of 138738769920 is 29967837831.

It is not an unprimeable number, because it can be changed into a prime (138738769927) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 527523709 + ... + 527523971.

It is an arithmetic number, because the mean of its divisors is an integer number (759057156).

Almost surely, 2^138738769920 is an apocalyptic number.

138738769920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138738769920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255043204416).

138738769920 is an abundant number, since it is smaller than the sum of its proper divisors (371347638912).

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

138738769920 is an frugal number, since it uses more digits than its factorization.

138738769920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362 (or 326 counting only the distinct ones).

The product of its (nonzero) digits is 27433728, while the sum is 63.

The spelling of 138738769920 in words is "one hundred thirty-eight billion, seven hundred thirty-eight million, seven hundred sixty-nine thousand, nine hundred twenty".