138444768 has 192 divisors, whose sum is σ = 503677440. Its totient is φ = 35942400.

The previous prime is 138444767. The next prime is 138444769. The reversal of 138444768 is 867444831.

138444768 is a `hidden beast` number, since 138 + 44 + 476 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (138444767) and next prime (138444769).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138444767) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 65488 + ... + 67568.

It is an arithmetic number, because the mean of its divisors is an integer number (2623320).

Almost surely, 2^138444768 is an apocalyptic number.

138444768 is a gapful number since it is divisible by the number (18) 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 138444768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251838720).

138444768 is an abundant number, since it is smaller than the sum of its proper divisors (365232672).

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

138444768 is a wasteful number, since it uses less digits than its factorization.

138444768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2118 (or 2104 counting only the distinct ones).

The product of its digits is 516096, while the sum is 45.

The square root of 138444768 is about 11766.2554791233. The cubic root of 138444768 is about 517.3195001674.

The spelling of 138444768 in words is "one hundred thirty-eight million, four hundred forty-four thousand, seven hundred sixty-eight".