12721433 has 4 divisors (see below), whose sum is σ = 12772368. Its totient is φ = 12670500.

The previous prime is 12721417. The next prime is 12721441. The reversal of 12721433 is 33412721.

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: 33412721 = 23 ⋅1452727.

It is a cyclic number.

It is not a de Polignac number, because 12721433 - 2⁴ = 12721417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12721399 and 12721408.

It is not an unprimeable number, because it can be changed into a prime (12721333) 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, 25091 + ... + 25592.

It is an arithmetic number, because the mean of its divisors is an integer number (3193092).

Almost surely, 2^12721433 is an apocalyptic number.

It is an amenable number.

12721433 is a deficient number, since it is larger than the sum of its proper divisors (50935).

12721433 is an equidigital number, since it uses as much as digits as its factorization.

12721433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50934.

The product of its digits is 1008, while the sum is 23.

The square root of 12721433 is about 3566.7117909918. The cubic root of 12721433 is about 233.4418295885.

The spelling of 12721433 in words is "twelve million, seven hundred twenty-one thousand, four hundred thirty-three".