135988 has 6 divisors (see below), whose sum is σ = 237986. Its totient is φ = 67992.

The previous prime is 135979. The next prime is 136013. The reversal of 135988 is 889531.

It can be written as a sum of positive squares in only one way, i.e., 121104 + 14884 = 348^2 + 122^2 .

It is a super-2 number, since 2×135988² = 36985472288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16995 + ... + 17002.

2¹³⁵⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

135988 is a deficient number, since it is larger than the sum of its proper divisors (101998).

135988 is a wasteful number, since it uses less digits than its factorization.

135988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34001 (or 33999 counting only the distinct ones).

The product of its digits is 8640, while the sum is 34.

The square root of 135988 is about 368.7655081485. The cubic root of 135988 is about 51.4241192501.

The spelling of 135988 in words is "one hundred thirty-five thousand, nine hundred eighty-eight".