12381778 has 8 divisors (see below), whose sum is σ = 18587772. Its totient is φ = 6185856.

The previous prime is 12381773. The next prime is 12381781. The reversal of 12381778 is 87718321.

It can be written as a sum of positive squares in 2 ways, for example, as 9467929 + 2913849 = 3077^2 + 1707^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (12381773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2826 + ... + 5722.

Almost surely, 2^12381778 is an apocalyptic number.

12381778 is a deficient number, since it is larger than the sum of its proper divisors (6205994).

12381778 is a wasteful number, since it uses less digits than its factorization.

12381778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5036.

The product of its digits is 18816, while the sum is 37.

The square root of 12381778 is about 3518.7750709586. The cubic root of 12381778 is about 231.3454723389.

The spelling of 12381778 in words is "twelve million, three hundred eighty-one thousand, seven hundred seventy-eight".