12145521 has 16 divisors (see below), whose sum is σ = 16954880. Its totient is φ = 7724160.

The previous prime is 12145513. The next prime is 12145537. The reversal of 12145521 is 12554121.

It is not a de Polignac number, because 12145521 - 2³ = 12145513 is a prime.

It is a super-2 number, since 2×12145521² = 295027360722882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12145501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5895 + ... + 7683.

It is an arithmetic number, because the mean of its divisors is an integer number (1059680).

Almost surely, 2^12145521 is an apocalyptic number.

It is an amenable number.

12145521 is a deficient number, since it is larger than the sum of its proper divisors (4809359).

12145521 is a wasteful number, since it uses less digits than its factorization.

12145521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1896.

The product of its digits is 400, while the sum is 21.

The square root of 12145521 is about 3485.0424674600. The cubic root of 12145521 is about 229.8645768638.

Adding to 12145521 its reverse (12554121), we get a palindrome (24699642).

The spelling of 12145521 in words is "twelve million, one hundred forty-five thousand, five hundred twenty-one".