138915841 has 4 divisors (see below), whose sum is σ = 138960900. Its totient is φ = 138870784.

The previous prime is 138915839. The next prime is 138915893. The reversal of 138915841 is 148519831.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 26471025 + 112444816 = 5145^2 + 10604^2 .

It is a cyclic number.

It is not a de Polignac number, because 138915841 - 2¹ = 138915839 is a prime.

It is a super-2 number, since 2×138915841² = 38595221761474562, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138915794 and 138915803.

It is not an unprimeable number, because it can be changed into a prime (138915541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17536 + ... + 24193.

It is an arithmetic number, because the mean of its divisors is an integer number (34740225).

Almost surely, 2^138915841 is an apocalyptic number.

It is an amenable number.

138915841 is a deficient number, since it is larger than the sum of its proper divisors (45059).

138915841 is an equidigital number, since it uses as much as digits as its factorization.

138915841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45058.

The product of its digits is 34560, while the sum is 40.

The square root of 138915841 is about 11786.2564455386. The cubic root of 138915841 is about 517.9055807493.

The spelling of 138915841 in words is "one hundred thirty-eight million, nine hundred fifteen thousand, eight hundred forty-one".