12798781 has 6 divisors (see below), whose sum is σ = 13155450. Its totient is φ = 12451536.

The previous prime is 12798767. The next prime is 12798791. The reversal of 12798781 is 18789721.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 9665881 + 3132900 = 3109^2 + 1770^2 .

It is not a de Polignac number, because 12798781 - 2²¹ = 10701629 is a prime.

It is a super-2 number, since 2×12798781² = 327617590171922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12798791) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 3306 + ... + 6043.

It is an arithmetic number, because the mean of its divisors is an integer number (2192575).

Almost surely, 2^12798781 is an apocalyptic number.

It is an amenable number.

12798781 is a deficient number, since it is larger than the sum of its proper divisors (356669).

12798781 is an frugal number, since it uses more digits than its factorization.

12798781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9423 (or 9386 counting only the distinct ones).

The product of its digits is 56448, while the sum is 43.

The square root of 12798781 is about 3577.5383995144. The cubic root of 12798781 is about 233.9139930346.

The spelling of 12798781 in words is "twelve million, seven hundred ninety-eight thousand, seven hundred eighty-one".