12023521 has 4 divisors (see below), whose sum is σ = 12044592. Its totient is φ = 12002452.

The previous prime is 12023513. The next prime is 12023569. The reversal of 12023521 is 12532021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12532021 = 463 ⋅27067.

It is a cyclic number.

It is not a de Polignac number, because 12023521 - 2³ = 12023513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12023495 and 12023504.

It is not an unprimeable number, because it can be changed into a prime (12023581) 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, 9655 + ... + 10828.

It is an arithmetic number, because the mean of its divisors is an integer number (3011148).

Almost surely, 2^12023521 is an apocalyptic number.

It is an amenable number.

12023521 is a deficient number, since it is larger than the sum of its proper divisors (21071).

12023521 is an equidigital number, since it uses as much as digits as its factorization.

12023521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21070.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 12023521 is about 3467.4949170835. The cubic root of 12023521 is about 229.0923332395.

Adding to 12023521 its reverse (12532021), we get a palindrome (24555542).

It can be divided in two parts, 12023 and 521, that added together give a square (12544 = 112²).

The spelling of 12023521 in words is "twelve million, twenty-three thousand, five hundred twenty-one".