135215440 has 20 divisors (see below), whose sum is σ = 314376084. Its totient is φ = 54086144.

The previous prime is 135215411. The next prime is 135215441. The reversal of 135215440 is 44512531.

It is a happy number.

135215440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 80928016 + 54287424 = 8996^2 + 7368^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135215441) 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 3 ways as a sum of consecutive naturals, for example, 845017 + ... + 845176.

Almost surely, 2^135215440 is an apocalyptic number.

135215440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

135215440 is an abundant number, since it is smaller than the sum of its proper divisors (179160644).

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

135215440 is a wasteful number, since it uses less digits than its factorization.

135215440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1690206 (or 1690200 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 135215440 is about 11628.2174042284. The cubic root of 135215440 is about 513.2655257974.

Adding to 135215440 its reverse (44512531), we get a palindrome (179727971).

The spelling of 135215440 in words is "one hundred thirty-five million, two hundred fifteen thousand, four hundred forty".