12015978 has 32 divisors (see below), whose sum is σ = 26105856. Its totient is φ = 3665088.

The previous prime is 12015977. The next prime is 12016013. The reversal of 12015978 is 87951021.

It is not an unprimeable number, because it can be changed into a prime (12015977) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9300 + ... + 10512.

It is an arithmetic number, because the mean of its divisors is an integer number (815808).

Almost surely, 2^12015978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12015978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13052928).

12015978 is an abundant number, since it is smaller than the sum of its proper divisors (14089878).

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

12015978 is a wasteful number, since it uses less digits than its factorization.

12015978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1358.

The product of its (nonzero) digits is 5040, while the sum is 33.

The square root of 12015978 is about 3466.4070736138. The cubic root of 12015978 is about 229.0444159126.

Adding to 12015978 its reverse (87951021), we get a palindrome (99966999).

The spelling of 12015978 in words is "twelve million, fifteen thousand, nine hundred seventy-eight".