38139840 has 336 divisors, whose sum is σ = 149778720. Its totient is φ = 8847360.

The previous prime is 38139833. The next prime is 38139847. The reversal of 38139840 is 4893183.

38139840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (38139833) and next prime (38139847).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 38139795 and 38139804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38139847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 930220 + ... + 930260.

It is an arithmetic number, because the mean of its divisors is an integer number (445770).

Almost surely, 2^38139840 is an apocalyptic number.

38139840 is a gapful number since it is divisible by the number (30) 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 38139840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74889360).

38139840 is an abundant number, since it is smaller than the sum of its proper divisors (111638880).

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

38139840 is a wasteful number, since it uses less digits than its factorization.

38139840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 38139840 is about 6175.7461087710. The cubic root of 38139840 is about 336.6094381480.

The spelling of 38139840 in words is "thirty-eight million, one hundred thirty-nine thousand, eight hundred forty".