12780840 has 64 divisors (see below), whose sum is σ = 38894400. Its totient is φ = 3359232.

The previous prime is 12780827. The next prime is 12780869. The reversal of 12780840 is 4808721.

It is a super-2 number, since 2×12780840² = 326699742211200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 12780798 and 12780807.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8031 + ... + 9489.

It is an arithmetic number, because the mean of its divisors is an integer number (607725).

Almost surely, 2^12780840 is an apocalyptic number.

12780840 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 12780840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19447200).

12780840 is an abundant number, since it is smaller than the sum of its proper divisors (26113560).

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

12780840 is a wasteful number, since it uses less digits than its factorization.

12780840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1546 (or 1542 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 12780840 is about 3575.0300698036. The cubic root of 12780840 is about 233.8046437302.

The spelling of 12780840 in words is "twelve million, seven hundred eighty thousand, eight hundred forty".