12781898 has 4 divisors (see below), whose sum is σ = 19172850. Its totient is φ = 6390948.

The previous prime is 12781897. The next prime is 12781903. The reversal of 12781898 is 89818721.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 7524049 + 5257849 = 2743^2 + 2293^2 .

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (12781891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3195473 + ... + 3195476.

Almost surely, 2^12781898 is an apocalyptic number.

12781898 is a deficient number, since it is larger than the sum of its proper divisors (6390952).

12781898 is an equidigital number, since it uses as much as digits as its factorization.

12781898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6390951.

The product of its digits is 64512, while the sum is 44.

The square root of 12781898 is about 3575.1780375248. The cubic root of 12781898 is about 233.8110950143.

The spelling of 12781898 in words is "twelve million, seven hundred eighty-one thousand, eight hundred ninety-eight".