12978261 has 12 divisors (see below), whose sum is σ = 18821088. Its totient is φ = 8617704.

The previous prime is 12978239. The next prime is 12978307. The reversal of 12978261 is 16287921.

It is a de Polignac number, because none of the positive numbers 2^k-12978261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12978211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 375 + ... + 5108.

It is an arithmetic number, because the mean of its divisors is an integer number (1568424).

Almost surely, 2^12978261 is an apocalyptic number.

It is an amenable number.

12978261 is a deficient number, since it is larger than the sum of its proper divisors (5842827).

12978261 is a wasteful number, since it uses less digits than its factorization.

12978261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5752 (or 5749 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 12978261 is about 3602.5353572172. The cubic root of 12978261 is about 235.0023298396.

The spelling of 12978261 in words is "twelve million, nine hundred seventy-eight thousand, two hundred sixty-one".