12139481 has 4 divisors (see below), whose sum is σ = 12182964. Its totient is φ = 12096000.

The previous prime is 12139447. The next prime is 12139483. The reversal of 12139481 is 18493121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18493121 = 151 ⋅122471.

It can be written as a sum of positive squares in 2 ways, for example, as 8317456 + 3822025 = 2884^2 + 1955^2 .

It is a cyclic number.

It is not a de Polignac number, because 12139481 - 2⁶ = 12139417 is a prime.

It is a super-2 number, since 2×12139481² = 294733997898722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12139483) 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, 21320 + ... + 21881.

It is an arithmetic number, because the mean of its divisors is an integer number (3045741).

Almost surely, 2^12139481 is an apocalyptic number.

It is an amenable number.

12139481 is a deficient number, since it is larger than the sum of its proper divisors (43483).

12139481 is an equidigital number, since it uses as much as digits as its factorization.

12139481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43482.

The product of its digits is 1728, while the sum is 29.

The square root of 12139481 is about 3484.1757992386. The cubic root of 12139481 is about 229.8264664565.

The spelling of 12139481 in words is "twelve million, one hundred thirty-nine thousand, four hundred eighty-one".