138525565 has 4 divisors (see below), whose sum is σ = 166230684. Its totient is φ = 110820448.

The previous prime is 138525559. The next prime is 138525581. The reversal of 138525565 is 565525831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 565525831 = 13 ⋅43501987.

It can be written as a sum of positive squares in 2 ways, for example, as 24740676 + 113784889 = 4974^2 + 10667^2 .

It is a cyclic number.

It is not a de Polignac number, because 138525565 - 2⁵ = 138525533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13852552 + ... + 13852561.

It is an arithmetic number, because the mean of its divisors is an integer number (41557671).

Almost surely, 2^138525565 is an apocalyptic number.

It is an amenable number.

138525565 is a deficient number, since it is larger than the sum of its proper divisors (27705119).

138525565 is an equidigital number, since it uses as much as digits as its factorization.

138525565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27705118.

The product of its digits is 180000, while the sum is 40.

The square root of 138525565 is about 11769.6883985941. The cubic root of 138525565 is about 517.4201172721.

The spelling of 138525565 in words is "one hundred thirty-eight million, five hundred twenty-five thousand, five hundred sixty-five".