12981440 has 56 divisors (see below), whose sum is σ = 31272480. Its totient is φ = 5132288.

The previous prime is 12981439. The next prime is 12981481. The reversal of 12981440 is 4418921.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35981 + ... + 36339.

Almost surely, 2^12981440 is an apocalyptic number.

12981440 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 12981440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15636240).

12981440 is an abundant number, since it is smaller than the sum of its proper divisors (18291040).

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

12981440 is a wasteful number, since it uses less digits than its factorization.

12981440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 12981440 is about 3602.9765472453. The cubic root of 12981440 is about 235.0215160623.

The spelling of 12981440 in words is "twelve million, nine hundred eighty-one thousand, four hundred forty".