12778705 has 8 divisors (see below), whose sum is σ = 15863400. Its totient is φ = 9870336.

The previous prime is 12778693. The next prime is 12778729. The reversal of 12778705 is 50787721.

12778705 = 48² + 49² + ... + 337².

It can be written as a sum of positive squares in 4 ways, for example, as 451584 + 12327121 = 672^2 + 3511^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12778705 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43920 + ... + 44209.

It is an arithmetic number, because the mean of its divisors is an integer number (1982925).

Almost surely, 2^12778705 is an apocalyptic number.

It is an amenable number.

12778705 is a deficient number, since it is larger than the sum of its proper divisors (3084695).

12778705 is an equidigital number, since it uses as much as digits as its factorization.

12778705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88163.

The product of its (nonzero) digits is 27440, while the sum is 37.

The square root of 12778705 is about 3574.7314584455. The cubic root of 12778705 is about 233.7916242231.

The spelling of 12778705 in words is "twelve million, seven hundred seventy-eight thousand, seven hundred five".