12815440 has 40 divisors (see below), whose sum is σ = 32506848. Its totient is φ = 4659840.

The previous prime is 12815437. The next prime is 12815447. The reversal of 12815440 is 4451821.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12815447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6402 + ... + 8161.

Almost surely, 2^12815440 is an apocalyptic number.

12815440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12815440 is an abundant number, since it is smaller than the sum of its proper divisors (19691408).

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

12815440 is a wasteful number, since it uses less digits than its factorization.

12815440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14587 (or 14581 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 12815440 is about 3579.8659192769. The cubic root of 12815440 is about 234.0154371680.

The spelling of 12815440 in words is "twelve million, eight hundred fifteen thousand, four hundred forty".