12791440 has 40 divisors (see below), whose sum is σ = 29998080. Its totient is φ = 5072256.

The previous prime is 12791423. The next prime is 12791459. The reversal of 12791440 is 4419721.

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

It is a junction number, because it is equal to n+sod(n) for n = 12791399 and 12791408.

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, 9531 + ... + 10789.

It is an arithmetic number, because the mean of its divisors is an integer number (749952).

Almost surely, 2^12791440 is an apocalyptic number.

12791440 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 12791440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14999040).

12791440 is an abundant number, since it is smaller than the sum of its proper divisors (17206640).

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

12791440 is a wasteful number, since it uses less digits than its factorization.

12791440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1399 (or 1393 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 12791440 is about 3576.5122675590. The cubic root of 12791440 is about 233.8692624457.

It can be divided in two parts, 12791 and 440, that added together give a palindrome (13231).

The spelling of 12791440 in words is "twelve million, seven hundred ninety-one thousand, four hundred forty".