12135440 has 20 divisors (see below), whose sum is σ = 28215084. Its totient is φ = 4854144.

The previous prime is 12135413. The next prime is 12135443. The reversal of 12135440 is 4453121.

It can be written as a sum of positive squares in 2 ways, for example, as 3444736 + 8690704 = 1856^2 + 2948^2 .

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

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

It is not an unprimeable number, because it can be changed into a prime (12135443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75767 + ... + 75926.

Almost surely, 2^12135440 is an apocalyptic number.

12135440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12135440 is an abundant number, since it is smaller than the sum of its proper divisors (16079644).

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

12135440 is a wasteful number, since it uses less digits than its factorization.

12135440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151706 (or 151700 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 12135440 is about 3483.5958433779. The cubic root of 12135440 is about 229.8009620212.

Adding to 12135440 its reverse (4453121), we get a palindrome (16588561).

The spelling of 12135440 in words is "twelve million, one hundred thirty-five thousand, four hundred forty".