138562817 has 4 divisors (see below), whose sum is σ = 142307796. Its totient is φ = 134817840.

The previous prime is 138562807. The next prime is 138562847. The reversal of 138562817 is 718265831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 718265831 = 167 ⋅4300993.

It can be written as a sum of positive squares in 2 ways, for example, as 68823616 + 69739201 = 8296^2 + 8351^2 .

It is a cyclic number.

It is not a de Polignac number, because 138562817 - 2⁸ = 138562561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138562807) 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, 1872434 + ... + 1872507.

It is an arithmetic number, because the mean of its divisors is an integer number (35576949).

Almost surely, 2^138562817 is an apocalyptic number.

It is an amenable number.

138562817 is a deficient number, since it is larger than the sum of its proper divisors (3744979).

138562817 is an equidigital number, since it uses as much as digits as its factorization.

138562817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3744978.

The product of its digits is 80640, while the sum is 41.

The square root of 138562817 is about 11771.2708319875. The cubic root of 138562817 is about 517.4664942873.

The spelling of 138562817 in words is "one hundred thirty-eight million, five hundred sixty-two thousand, eight hundred seventeen".