12278131 has 4 divisors (see below), whose sum is σ = 13000392. Its totient is φ = 11555872.

The previous prime is 12278129. The next prime is 12278137. The reversal of 12278131 is 13187221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12278131 - 2¹ = 12278129 is a prime.

It is a super-2 number, since 2×12278131² = 301505001706322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12278096 and 12278105.

It is not an unprimeable number, because it can be changed into a prime (12278137) 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, 361105 + ... + 361138.

It is an arithmetic number, because the mean of its divisors is an integer number (3250098).

Almost surely, 2^12278131 is an apocalyptic number.

12278131 is a deficient number, since it is larger than the sum of its proper divisors (722261).

12278131 is an equidigital number, since it uses as much as digits as its factorization.

12278131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722260.

The product of its digits is 672, while the sum is 25.

The square root of 12278131 is about 3504.0164097789. The cubic root of 12278131 is about 230.6981370945.

The spelling of 12278131 in words is "twelve million, two hundred seventy-eight thousand, one hundred thirty-one".