12728840 has 32 divisors (see below), whose sum is σ = 28788480. Its totient is φ = 5065152.

The previous prime is 12728831. The next prime is 12728857. The reversal of 12728840 is 4882721.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 12728797 and 12728806.

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, 8207 + ... + 9633.

It is an arithmetic number, because the mean of its divisors is an integer number (899640).

Almost surely, 2^12728840 is an apocalyptic number.

12728840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12728840 is an abundant number, since it is smaller than the sum of its proper divisors (16059640).

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

12728840 is a wasteful number, since it uses less digits than its factorization.

12728840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661 (or 1657 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 12728840 is about 3567.7499912410. The cubic root of 12728840 is about 233.4871276340.

The spelling of 12728840 in words is "twelve million, seven hundred twenty-eight thousand, eight hundred forty".