135661518 has 24 divisors (see below), whose sum is σ = 303416256. Its totient is φ = 43761600.

The previous prime is 135661481. The next prime is 135661523. The reversal of 135661518 is 815166531.

135661518 is a `hidden beast` number, since 1 + 35 + 6 + 615 + 1 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 121003 + ... + 122118.

It is an arithmetic number, because the mean of its divisors is an integer number (12642344).

Almost surely, 2^135661518 is an apocalyptic number.

135661518 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

135661518 is an abundant number, since it is smaller than the sum of its proper divisors (167754738).

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

135661518 is a wasteful number, since it uses less digits than its factorization.

135661518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243160 (or 243157 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 135661518 is about 11647.3824527230. The cubic root of 135661518 is about 513.8293301050.

It can be divided in two parts, 135 and 661518, that multiplied together give a triangular number (89304930 = T₁₃₃₆₄).

The spelling of 135661518 in words is "one hundred thirty-five million, six hundred sixty-one thousand, five hundred eighteen".