135991525 has 12 divisors (see below), whose sum is σ = 175961952. Its totient is φ = 104062640.

The previous prime is 135991523. The next prime is 135991529. The reversal of 135991525 is 525199531.

It is not a de Polignac number, because 135991525 - 2¹ = 135991523 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 (135991523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 117679 + ... + 118828.

It is an arithmetic number, because the mean of its divisors is an integer number (14663496).

Almost surely, 2^135991525 is an apocalyptic number.

It is an amenable number.

135991525 is a deficient number, since it is larger than the sum of its proper divisors (39970427).

135991525 is a wasteful number, since it uses less digits than its factorization.

135991525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236540 (or 236535 counting only the distinct ones).

The product of its digits is 60750, while the sum is 40.

The square root of 135991525 is about 11661.5404214023. The cubic root of 135991525 is about 514.2456357473.

It can be divided in two parts, 135991 and 525, that multiplied together give a triangular number (71395275 = T₁₁₉₄₉).

The spelling of 135991525 in words is "one hundred thirty-five million, nine hundred ninety-one thousand, five hundred twenty-five".