138995893 has 4 divisors (see below), whose sum is σ = 147172140. Its totient is φ = 130819648.

The previous prime is 138995891. The next prime is 138995921. The reversal of 138995893 is 398599831.

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 115734564 + 23261329 = 10758^2 + 4823^2 .

It is a cyclic number.

It is not a de Polignac number, because 138995893 - 2¹ = 138995891 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138995891) 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, 4088098 + ... + 4088131.

It is an arithmetic number, because the mean of its divisors is an integer number (36793035).

Almost surely, 2^138995893 is an apocalyptic number.

It is an amenable number.

138995893 is a deficient number, since it is larger than the sum of its proper divisors (8176247).

138995893 is an equidigital number, since it uses as much as digits as its factorization.

138995893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8176246.

The product of its digits is 2099520, while the sum is 55.

The square root of 138995893 is about 11789.6519456683. The cubic root of 138995893 is about 518.0050448468.

The spelling of 138995893 in words is "one hundred thirty-eight million, nine hundred ninety-five thousand, eight hundred ninety-three".