135605171520 has 1680 divisors, whose sum is σ = 621580151808. Its totient is φ = 27799511040.

The previous prime is 135605171519. The next prime is 135605171531. The reversal of 135605171520 is 25171506531.

It is a happy number.

135605171520 is a `hidden beast` number, since 1 + 3 + 5 + 60 + 5 + 1 + 71 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (1680).

It is a super-3 number, since 3×135605171520³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 709974625 + ... + 709974815.

Almost surely, 2^135605171520 is an apocalyptic number.

135605171520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 135605171520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310790075904).

135605171520 is an abundant number, since it is smaller than the sum of its proper divisors (485974980288).

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

135605171520 is a wasteful number, since it uses less digits than its factorization.

135605171520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290 (or 264 counting only the distinct ones).

The product of its (nonzero) digits is 31500, while the sum is 36.

The spelling of 135605171520 in words is "one hundred thirty-five billion, six hundred five million, one hundred seventy-one thousand, five hundred twenty".