135213520 has 120 divisors (see below), whose sum is σ = 347596056. Its totient is φ = 48881664.

The previous prime is 135213493. The next prime is 135213521. The reversal of 135213520 is 25312531.

It can be written as a sum of positive squares in 12 ways, for example, as 66389904 + 68823616 = 8148^2 + 8296^2 .

It is a junction number, because it is equal to n+sod(n) for n = 135213491 and 135213500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135213521) 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 23 ways as a sum of consecutive naturals, for example, 986892 + ... + 987028.

Almost surely, 2^135213520 is an apocalyptic number.

135213520 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 135213520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173798028).

135213520 is an abundant number, since it is smaller than the sum of its proper divisors (212382536).

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

135213520 is a wasteful number, since it uses less digits than its factorization.

135213520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 135213520 is about 11628.1348461393. The cubic root of 135213520 is about 513.2630964040.

The spelling of 135213520 in words is "one hundred thirty-five million, two hundred thirteen thousand, five hundred twenty".