135520220 has 72 divisors (see below), whose sum is σ = 321303024. Its totient is φ = 47616000.

The previous prime is 135520199. The next prime is 135520237. The reversal of 135520220 is 22025531.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 135520192 and 135520201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 211100 + ... + 211740.

It is an arithmetic number, because the mean of its divisors is an integer number (4462542).

Almost surely, 2^135520220 is an apocalyptic number.

135520220 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 135520220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160651512).

135520220 is an abundant number, since it is smaller than the sum of its proper divisors (185782804).

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

135520220 is a wasteful number, since it uses less digits than its factorization.

135520220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723 (or 690 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 135520220 is about 11641.3152177922. The cubic root of 135520220 is about 513.6508754755.

Adding to 135520220 its reverse (22025531), we get a palindrome (157545751).

The spelling of 135520220 in words is "one hundred thirty-five million, five hundred twenty thousand, two hundred twenty".