12421533 has 4 divisors (see below), whose sum is σ = 16562048. Its totient is φ = 8281020.

The previous prime is 12421517. The next prime is 12421537. The reversal of 12421533 is 33512421.

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.

It is not a de Polignac number, because 12421533 - 2⁴ = 12421517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12421537) 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, 2070253 + ... + 2070258.

It is an arithmetic number, because the mean of its divisors is an integer number (4140512).

Almost surely, 2^12421533 is an apocalyptic number.

It is an amenable number.

12421533 is a deficient number, since it is larger than the sum of its proper divisors (4140515).

12421533 is an equidigital number, since it uses as much as digits as its factorization.

12421533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4140514.

The product of its digits is 720, while the sum is 21.

The square root of 12421533 is about 3524.4195266739. The cubic root of 12421533 is about 231.5928065932.

Adding to 12421533 its reverse (33512421), we get a palindrome (45933954).

It can be divided in two parts, 1242 and 1533, that added together give a triangular number (2775 = T₇₄).

The spelling of 12421533 in words is "twelve million, four hundred twenty-one thousand, five hundred thirty-three".