12291481 has 4 divisors (see below), whose sum is σ = 12299364. Its totient is φ = 12283600.

The previous prime is 12291463. The next prime is 12291491. The reversal of 12291481 is 18419221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 9455625 + 2835856 = 3075^2 + 1684^2 .

It is a cyclic number.

It is not a de Polignac number, because 12291481 - 2¹³ = 12283289 is a prime.

It is a super-2 number, since 2×12291481² = 302161010346722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12291451) 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, 730 + ... + 5011.

It is an arithmetic number, because the mean of its divisors is an integer number (3074841).

Almost surely, 2^12291481 is an apocalyptic number.

It is an amenable number.

12291481 is a deficient number, since it is larger than the sum of its proper divisors (7883).

12291481 is an equidigital number, since it uses as much as digits as its factorization.

12291481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7882.

The product of its digits is 1152, while the sum is 28.

The square root of 12291481 is about 3505.9208490780. The cubic root of 12291481 is about 230.7817194295.

The spelling of 12291481 in words is "twelve million, two hundred ninety-one thousand, four hundred eighty-one".