12272778 has 48 divisors (see below), whose sum is σ = 30588480. Its totient is φ = 3483648.

The previous prime is 12272749. The next prime is 12272779. The reversal of 12272778 is 87727221.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12272779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32193 + ... + 32571.

It is an arithmetic number, because the mean of its divisors is an integer number (637260).

Almost surely, 2^12272778 is an apocalyptic number.

12272778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 12272778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15294240).

12272778 is an abundant number, since it is smaller than the sum of its proper divisors (18315702).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12272778 is a wasteful number, since it uses less digits than its factorization.

12272778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651 (or 648 counting only the distinct ones).

The product of its digits is 21952, while the sum is 36.

The square root of 12272778 is about 3503.2524887596. The cubic root of 12272778 is about 230.6646057523.

Adding to 12272778 its reverse (87727221), we get a palindrome (99999999).

It can be divided in two parts, 1227 and 2778, that added together give a triangular number (4005 = T₈₉).

The spelling of 12272778 in words is "twelve million, two hundred seventy-two thousand, seven hundred seventy-eight".