135991658 has 24 divisors (see below), whose sum is σ = 226247364. Its totient is φ = 61255040.

The previous prime is 135991651. The next prime is 135991679. The reversal of 135991658 is 856199531.

It can be written as a sum of positive squares in 2 ways, for example, as 127622209 + 8369449 = 11297^2 + 2893^2 .

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135991651) 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, 24860 + ... + 29832.

Almost surely, 2^135991658 is an apocalyptic number.

135991658 is a deficient number, since it is larger than the sum of its proper divisors (90255706).

135991658 is a wasteful number, since it uses less digits than its factorization.

135991658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5110 (or 5099 counting only the distinct ones).

The product of its digits is 291600, while the sum is 47.

The square root of 135991658 is about 11661.5461239066. The cubic root of 135991658 is about 514.2458033916.

The spelling of 135991658 in words is "one hundred thirty-five million, nine hundred ninety-one thousand, six hundred fifty-eight".