135990 has 24 divisors (see below), whose sum is σ = 353808. Its totient is φ = 36240.

The previous prime is 135979. The next prime is 136013. The reversal of 135990 is 99531.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

135990 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 666 + ... + 845.

It is an arithmetic number, because the mean of its divisors is an integer number (14742).

2¹³⁵⁹⁹⁰ is an apocalyptic number.

135990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

135990 is an abundant number, since it is smaller than the sum of its proper divisors (217818).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

135990 is a wasteful number, since it uses less digits than its factorization.

135990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1524 (or 1521 counting only the distinct ones).

The product of its (nonzero) digits is 1215, while the sum is 27.

The square root of 135990 is about 368.7682198889. The cubic root of 135990 is about 51.4243713501.

The spelling of 135990 in words is "one hundred thirty-five thousand, nine hundred ninety".