12780644 has 6 divisors (see below), whose sum is σ = 22366134. Its totient is φ = 6390320.

The previous prime is 12780637. The next prime is 12780661. The reversal of 12780644 is 44608721.

It can be written as a sum of positive squares in only one way, i.e., 11142244 + 1638400 = 3338^2 + 1280^2 .

It is a super-2 number, since 2×12780644² = 326689722109472, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12780644.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1597577 + ... + 1597584.

It is an arithmetic number, because the mean of its divisors is an integer number (3727689).

Almost surely, 2^12780644 is an apocalyptic number.

It is an amenable number.

12780644 is a deficient number, since it is larger than the sum of its proper divisors (9585490).

12780644 is a wasteful number, since it uses less digits than its factorization.

12780644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3195165 (or 3195163 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 12780644 is about 3575.0026573417. The cubic root of 12780644 is about 233.8034485572.

The spelling of 12780644 in words is "twelve million, seven hundred eighty thousand, six hundred forty-four".