12291378 has 64 divisors (see below), whose sum is σ = 28283904. Its totient is φ = 3528000.

The previous prime is 12291343. The next prime is 12291379. The reversal of 12291378 is 87319221.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12291379) 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 31 ways as a sum of consecutive naturals, for example, 173083 + ... + 173153.

It is an arithmetic number, because the mean of its divisors is an integer number (441936).

Almost surely, 2^12291378 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12291378, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14141952).

12291378 is an abundant number, since it is smaller than the sum of its proper divisors (15992526).

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

12291378 is a wasteful number, since it uses less digits than its factorization.

12291378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191.

The product of its digits is 6048, while the sum is 33.

The square root of 12291378 is about 3505.9061596112. The cubic root of 12291378 is about 230.7810747938.

The spelling of 12291378 in words is "twelve million, two hundred ninety-one thousand, three hundred seventy-eight".