138019992 has 64 divisors (see below), whose sum is σ = 377602560. Its totient is φ = 41692800.

The previous prime is 138019969. The next prime is 138019993. The reversal of 138019992 is 299910831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138019993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 113178 + ... + 114390.

It is an arithmetic number, because the mean of its divisors is an integer number (5900040).

Almost surely, 2^138019992 is an apocalyptic number.

138019992 is a gapful number since it is divisible by the number (12) 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 138019992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188801280).

138019992 is an abundant number, since it is smaller than the sum of its proper divisors (239582568).

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

138019992 is a wasteful number, since it uses less digits than its factorization.

138019992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1664 (or 1660 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 42.

The square root of 138019992 is about 11748.1910096832. The cubic root of 138019992 is about 516.7898785348.

It can be divided in two parts, 1380199 and 92, that added together give a triangular number (1380291 = T₁₆₆₁).

The spelling of 138019992 in words is "one hundred thirty-eight million, nineteen thousand, nine hundred ninety-two".