12661440 has 168 divisors, whose sum is σ = 44592240. Its totient is φ = 3041280.

The previous prime is 12661433. The next prime is 12661469. The reversal of 12661440 is 4416621.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 12661440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 116106 + ... + 116214.

It is an arithmetic number, because the mean of its divisors is an integer number (265430).

Almost surely, 2^12661440 is an apocalyptic number.

12661440 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 12661440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22296120).

12661440 is an abundant number, since it is smaller than the sum of its proper divisors (31930800).

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

12661440 is a wasteful number, since it uses less digits than its factorization.

12661440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 12661440 is about 3558.2917249714. The cubic root of 12661440 is about 233.0742884806.

The spelling of 12661440 in words is "twelve million, six hundred sixty-one thousand, four hundred forty".